The LT4 was built that way because the Vette engine team got pissed off at the very idea of the LT5 not being a Chevy built engine. This was their way of giving Dave McClellan the finger: “See, we could have build that ZR1 engine if you’d let us!”
Dave McClellan had nothing to do with the LT5 . He was Corvette Chief engineer from 75 to early 90's . Graham Behan of Lotus worked on the LT5 . Graham and the Lotus team were busy working on a 475 h.p. second gen LT5 for the new Corvette when the LT5 was canceled in 1993 . Yes way back in 93 . Chevrolet engine team was already working on the LS series of engines when the LT5 was terminated. So the remaining LT5's were used up in the following 93 , 94 , and 95 ZR1'S. McClellan likes to give himself credit where none is due when it comes to the ZR1 power train .
I knew it! I had a 1996 LT1 Corvette and now own a 1996 LT4 Corvette. I kept saying that the LT4 had more like 370 hp rather than the 330 hp rating the factory had... it was much faster than the LT1. Awesome to know... thanks Lyle.
My first new car I bought was a 1996 Z28 with the LT-1 rated at 285hp and a 6-speed manual. I remember seeing a Grand Sport Corvette on the showroom floor at the time. I told myself that I was eventually going to own a LT-4 Corvette in my lifetime but I couldn’t afford one at the time and my Z-28 stickered at $28,502 when a base Corvette was over $40,000. I was finally able to afford a 1996 base Corvette in Torch Red with an LT-4 and 6-speed manual in 2016 with 18,000 original miles. The LT-4 is insanely faster than the LT-1 in my Z-28. It’s almost like they’re not even remotely the same engine. I understand the 1996 Corvette automatic LT-1 is rated at 300hp but there is something special about the LT-4.
I’m happy to see this video. 20-ish years ago I had both a ‘96 CE LT4 and a 99 6-SPD coupe. I ALWAYS felt like my C4 was quicker but never saw any data to confirm that.
I purchased a torch red LT4 last year with only 19K miles for $25K. A garage Queen in pure stock form. No mods except for window tinting as I live in Arizona. This car is quick but not up to par with today’s vets but definitely capable of staying or even out performing a stock C5.
I’ve got a C4 Grand Sport with the LT4 and definitely learned a few things from this video, thank you Lyle! Always suspected the factory rating was low on these engines.
The Grand Sport in 1996 is 100% a an appearance package. That's it. You could get a "Base" or "Vert" 96 Corvette with the same options as the Grand Sport with the exception of the hideous Pep Boys rear wheel flairs the GC Coupes had. Thankfully, these days you can buy A-Molds that will fit a 315 tire and tuck under the stock fenders. That said, when these cars were new in 1996 we called the LT-4 Cars "Grand Sports". Got completely smoked by a C4 back in 1996-7? It was likely a "Grand Sport" as the saying went. I remember rolling in my buddies dad's Turbo Supra and a White Vette with brand new tags came up next to us at a light. As it pulled away his dad said "Must be one of them new Grand Sport cars". Hell, even the model kits of the day reflect this. I have a Comp Yellow 96 with 14k miles on the clock in the garage. It's a hoot. Great Video!
My LT4 quit working. No signal to the optispark. So now she sits in storage waiting to go to a resto shop. She sure was fun. Interesting, my son, in his 96 Collectors Edition, posted faster lap times at the National Corvette Museum race track, than I did in my LT4. Another interesting fact. When Museum archive sent me the build sheet and window sticker for the LT4, I noticed that car started its life 11 hours earlier than my son! I gave the car to him when he graduated from OSU. How cool to have a Corvette built on your actual birthday!!!
I bought a used LT4 Torch Red convertible a while back. The previous owner, who was a moderator on the Corvette Forum, bought it back from me a year later. That was a sweet car. Gordon Killebrew looked it over at a clinic he held and pronounced it "a garage kept car". He was impressed.
Great video. Just as this video came out, I purchased a torch red 96 LT4 out of Arizona with only 25,034 miles. It was in a Texas garage, then in a North Carolina garage, then in an Arizona garage before being shipped to my garage. My car is close if not as fast as a 90 zr1. If you can find one in excellent condition under$18,000, you will have a great performance car for the money.
I'm lucky enough to own an LT4 Collector Edition coupe. One of the surprising things about my car, which is admittedly a little on the tired side, was the performance of it on a long country drive organized by a late Corvette friend of mine. He had a Commemorative Edition Z06 which I believe had a few simple bolt ons but wasn't heavily breathed on. Near the end of that drive we got onto a 4 lane divided highway, and bearing in mind we're running with 3 Vipers we got going quite quickly. Between 100-130 my car had no trouble matching pace with his Z06. Now that wasn't a scientific test or even a proper roll race, but when he stood on it, I could keep my car in 4th and keep up with no issues. The high speed performance of this car has really, really impressed me, and while it still needs some TLC (vacuum leak, I believe) I find it very easy to believe that it's still putting out more power than the rated 330 hp. Now with that said, the car now has about 85k miles, and while I did take it to the drag strip I'm just too afraid of destroying the clutch to launch it really hard, and having never run at a drag strip before my times sucked. On the open road, though, this car rips. I would upgrade the brakes before adding power. A year of LT4 ownership convinced me to buy an MX-5 RF. I love the targa way more than I thought but it's just too fast for me as a daily. Besides, it's a special car and I want to keep it that way. EDIT - My neighbor picked up a 2007 C6 with a 6 speed this week. Went for a drive with him today and there's very little difference between the two (less than half a car length) from 70-125 in fourth gear in each but I don't know how the gearing compares.
Shhh! Your giving away all the secrets! I worked for a Chevy dealer in '96 as a salesman with another guy who was also a gearhead like me. We were checking out the specs on the LT4 and researched as much as we could since it was so interesting. (You forgot to mention the sodium filled exhaust valves) We both came to the conclusion that Chevrolet was sand bagging on the horsepower! I often wondered how it would perform with a slightly lower rear end gear to take advantage of the high rpm capabilities. I bet it could be a real beast on the drag strip that way. Unfortunately it was a small dealership and we never saw one.
Thank you Thank you! I have the LT4 in a collectors edition and LOVE it! IThank you for this video. I installed new tires and am going to dyno mine soon I will update with RWHP from Kelly Moss Racnig .
Enjoyed this! An engine series would be cool. You should cover the L88 and ZL1 engines! The 2nd and only ZL1 Convertible sold a while back for about 3 mil!
My budgeted journey 2 years ago to attain a dream car from one of many posters in my room when i was 15 in the 90s led me to the C4. I wanted a stick and i wanted the best version of it. (ZR1 outside of budget)... conclusion = LT4. One day just happened to ride by a mechanic shop out of town on the way to a job and saw a torch red C4 parked outside that had some kind of marking on the right side of the back bumper. It didn't have any sale sign but i called anyway and yada yada, 2 weeks later its in my garage. Love my LT4. The whole story around the LT4 makes it even better.
Once again Lyle, a very, very informative video. I love your in-depth analysis of the LT4 engine. I had no idea that they had roller rockers. Obviously the LT4 was real turning point for GM as to what was coming down the road. Well done Lyle. 👍👍 Save the Wave 🙋♂
Alot of the tech of the Lt4, went into the LS1 and LS6 . Also if you can't find a Lt4 engine Corvette. GM saved same Lt4 engines for the 1997 Pontiac Firehawk, and the 1997 Camaro SLP SS.
Awesome video Lyle. Bought my torch red 96 Lt4 a few years ago and still have it. Don't drive it much as I'm getting older and these cars are not user friendly when it comes to getting in and out of them. Do love the power and changing the gears when I do drive it. Thanks again for the info.
Great video, thank you! I have also read that GM held focus groups to decide whether to go with an overhead cam multi valve for the upcoming C5. People preferred the power delivery of the pushrod motor, just wanted more without sacrificing low end power.
Great video Lyle. I love when GM does this. Like getting the good gift in a grab bag. The way they made the 82 with the same drivetrain as the next generation, I wish the Crossfire would have worked out for them. It was exciting as a child the way they marketed these things in the 80's. I thought they should have made all 04 manuals with a Ls6. But we got the Top mount battery cables, and faulty gas tank crossover...no love loss for the C5 despite that. I believe there are no bad Corvettes, but my strongest desire is for the final year of each generation, especially the 1996/LT4 6spd.
The LT4 really is special. To be fair though, the LT1 made well over 330 on the engine Dyno, in fact 330 is a lower number for a later healthy stock LT1.
Thanks for the great info. I have a 96 collector's edition. Took her to the texas mile back in 16. Managed to get a 154 and a 156 mph in a mile. Then let a freind drive her and on his second run spun a rod bearing for me. Fast forward to 2 weeks ago and I have finally found a stock crankshaft. Now I can start the rebuild. Yea
Hello all. Hey what a great video. Thank you for making such an honest detailed aldescription of the lt4. I own a 96 white with red low mileage lt4. And an 08 ls3 Jetstream blue. Of course I love them both but the c4 is still funner to drive overall and especially at slower speeds. It just feels like a ton of torque. Radiates thru you Wraps itself on and around you I love the sound too. Like a jet engine lt4 owners know what I'm talking about . I'm virtually bone stock with upgraded plugs. Wires air intake . I'm 56 owned and drove a lot in my life this car is truly spectacular. I had it dynoed last year 3 x and it came out between 402 and 410 hp. And it feels like it. Head to toe. It feels. Feels. Like it has more torque below 2000 rpm then my C6. But my ls3 takes off like a rocket and is faster. Overall. Brutal after 5 k rpm. Lt4 underated yes. In all areas. Great video .
I did a lot of research before deciding to purchase my C4 Gen '96. I knew after reading all the articles and comments from others this was a special hidden gem! Thanks for confirming 👍 I own a '96 Collector Edition with just a little over 89k. Am I happy? What do you think 😊 Great info and thanks.
I don’t doubt your conclusions or the facts that you cite. Another great video, and thank you. What is baffling is not that these engines made more HP than advertised. What’s baffling is why there was such a dramatic disparity among LT4’s (330 to 390?!?) What accounts for this?
I do believe the differences in HP numbers. I’ve owned about 15 LT4s over the years and there were a couple that just felt faster. Like ZR1 fast. Hard to believe factory didn’t have better control of that but I’m not complaining.
Great CZcams as always Lyle, im pretty sure that the C4LT5 was also underrated, bring on your stock LT4 Vette, the Zr1 will kill it anyway you want to run... Again, keep up the Great channel, you are the vette man
I've been eyeing Corvettes for a few months and hope to make a purchase soon. I'm torn between a 96 LT4 or an 02-04 Z06. There is also a 92 ZR1, but not sure I want to potentially daily one. I know the Z06 is faster and has more room, which is a plus since I'm 6'1" 260lbs. However, the silver 96 with red and black interior is gorgeous! Tough call.
Yeah my name is Brandon I have a 96 convert LT4 that I just had rebuilt by machine shop and I was running it with my friends 02 convert with the LS1 and I did beat him just barely a few times in a row and he agreed that my car was faster than his kind of blew our minds but love the car it also came with the CC 2 option so with the LT 4 and the CC 2 I believe it's a pretty rare car
To LT4s were meant to rev They just picked the lower RPM number to get the 3:30 It had a lighter weight valve train and crankshaft The thing would spin
I've own one for 9 years the lt4 have rocker 1.6 instead of 1.5 with taller valve cover and a cut-off at 6400 rpm done hot cam from performance part shorty header and a good aftermarket clutch with steel flywheel dam this car miss me soo munch!!! the third and fourth speed was a blast!!! lost 1 time and almost a second time my driving liscence cant keep that thing ....
Lyle I injoy your videos and I am not a vet owner but will be looking for a 96 lt4 , please let me know your price range when you're thrue with the one your working on. Ps I am retired , looking to drive cross country!
Are there manufacturing dates or vin numbers on the engines of the lt4 that correspond with the higher horsepower versions? Is there a way to tell what you might have without actually going to the dyno?
Wow, I've watched a lot of Videos on LT4 cars but that's a hell of a lot more info than I've found out before! I missed out on one before finding my C5. What's the weight difference between a C4 LT4 and a normal manual C5?
Bought a 96 LT4 used in 98 with 24k miles I think and at 55k miles 1 roller lifter had some tiny chunks of metal come out of the roller and take out 2 cam lobes. Very disappointing, especially the dealer and GM's response which was too old, too many miles, sorry, nothing we can do. Had it fixed on my own and ended up selling it in 2004 for a reason that never materialize...so should have kept it. Anyone else hear of any roller lifter issues? "Rumor" back then was that the cam and lifters were Comp Cams.
As an LT4 owner I appreciated this video! Do you have any theories on why there was so much VARIANCE between the LT4 engines that were tested? I realize that manufacturing tolerances can make some engines make more power than others, but a 70 hp difference seems MASSIVE for the same engine design!
I’m kinda thinking 400hp out only them is hard to believe. 360hp is one thing. I mean did they do percentage estimates or actually pull the motor and do at engine power tests? 🤷♂️
Well, here I go again: In 1995 I acquired 2 LT1'S. Testing and 1 to keep. Blue and a Black. bot autos both 2:59 rears. The blue was a real bow wow. The black/red was and became a bigger beast. Still have it actually. Bone stock the black/red ran consistent 13:38’s @ 104 mph. Best time ever was 13:10 at 110mph. Month of December. I did use a hypertech programmer. Red line was 6300. Track was Capital Raceway, Crofton, MD. Little C4 was knocking down big C4’s with 383’s. One ran 13.6’s @ 110. My clock was faster, but their mph was faster. Who won? Of course, the quicker clock in this case. My first adventure into 383’s, a short stroke unit. 5.56 I beam rods, with hypereutectic pistons got me to 400 hp and 466 lb trq. Still being hungry I got a 97 Camaro Z LT1 and built a long stroke 383/388. Not sure because Probe Industries and Vigilante Racing have different numbers for the same config. This one made 530 hp and with some unique additions; namely individual coil packs; and specialty plugs from NGK i estimate it at 560 hp. Heads are Trick Flow 185; given the smokey bear treatment, up to 2:08 titanium valves. Build and dyno can be seen here. paceage.com/a-383-388-c4-lt1-560-hp/ Engine still has 0 miles since being finished some years ago. Guess I need to sell; but promised never. Travel bug got me. Loss interest. Hate that. Torque converter is Yank SS3600. Swapped out Dana 36 for 44 with 3:42. Set car up hoping for 1 to 1100 or so STS hp. A known builder doing my research told me they have a club of 1000 hp C4's; one or 2 in the 1100 hp ranges. I have had at least one C5's but still love my C4's. One more thing. If you want to hear what the engine sounds like in car. go here; www.ghostcopstv.com/ There are 2 trailers there. I was in the Virginia Beach area; came to Florida for a visit and wanted to come back. Actually I landed in Sarasota; in July. Believe it or not; I have been by C & S, without even knowing they were there. Today in part. So I get on YT and without knowing how; there is this cool guy talking 1996 LT4’s. Hope to get by C&S soon. Thanks all.
Did GM ever offer an explanation as to why the LT4 had such a great of horsepower variation on engines that should be very close to being the same ? Are there any LS1s with that 345-350 plus almost 50 hp more that exist. Those greater hp engines were not by accident in the LT4s.
They did make a Silver Grand Sport ( Collectors Edition) with 6 Speed , LT4 Aluminum Heads 330 HP and 340 t ft and it also had Silver Painted Grand Sport Wheels not of chrome
The Collector's Edition and Grand Sport were separate options. Both could be had with the LT4, but the CE did not have the wider rear wheels of the Grand Sport Coupe. The CE car was a paint and appearance package for the most part, with the satin ZR-1 style wheels added. The Grand Sport was a limited production model, while the CE was not. Similar, but different. Lyle
@@WarriorsPhoto , I sold 901 back to buy a vette in 2018. They sold it to a guy in Gainesville, Texas. I had a 77 L82, 96 Lt4, 2000 hardtop, and 96 Grand Sport. I now have a 2019 Mustang GT.
@@WarriorsPhoto, the 2000 FRC, because that is what Chevy used to make the C5 Zo6 the next year. It was lighter than the C5 coupe, and handled the best. I liked the Grand Sport but was afraid of someone hitting it!
@@markbaumgartner7261 I feel the same way about the C5 FRC. It was lightweight and handled well. It also felt peppier since the car lost some weight over a standard C5. It helped show how good 350 HP was on the road. Do you regret getting rid of it?
Hey buddy great video as always im about to jump back into the market for a 03 04 zo6 , did you do any videos on that gen i remember you saying you own one at the shop. Thanks for any input
I've done several buyer's guides and "what to look for" videos on the C5, 99% of which pertains to the 03/04 Z06. Those are the two best years, and beyond sniffing out whatever mechanical needs a car may have to make it "perfect", they have very few issues. Happy Hunting! Lyle
Great clip!! Orlando here - wish you were closer! How can I find out the "actual" horse power of my Lt4? I have a "Collector Edition" Convertible Lt4 with light gray interior and only 9700 miles. Also have the original Goodyear Eagle GS-C tires!
I’m lucky enough to have a 96 LT 4 convertible and a 91 ZR-1. Also have a 95 LT1 Firebird . Although the LT 4 definitely feels faster than the LT 1 I don’t think it’s as quick as the ZR-1. A club member who has an LT4 collector edition than replaced it with an 03 LS1 car has said to me that he didn’t think the LS1 was faster, he felt they were similar.
Wow, excellent article. My only question is, if I am shopping for a 1996 Corvette, is there a way to determine if it has one of the more potent LT4 engines?
Lyle, was the LT4 fuel pump different than the LT1? I've heard this a couple of times, but you didn't mention it in the video. I have a 96 Grand Sport and attempted to replace the fuel pump with a Delco unit from one of the major on-line suppliers. Not only did the replacement pump look different, but it had a ground issue that made the fuel gauge read 'empty' with a half tank of fuel in the tank. I returned it for a replacement and the replacement did the same thing. Resistance was bench checked before installation and it showed a full range of resistance from zero up to around 80-90 ohms, yet when installed, low single digit readings and empty tank at the gauge. When I installed the original pump back it, it correctly indicated the half tank of fuel. Is the LT4 pump a higher flow unit to support the higher flow injectors?
I belive back in 1993 or 1994 the was a Grand Sport "Prototype" advertized. It was Represented to have an "LT4 V8 350 HP". So it was always in the books to be a 350 ish hp motor. But after spending millions developing the new LS platform that was to deliver 345 hp, GM had to under rate the LT4 due to the higher actual HP output. It would have customers questioning whether or not to buy the new corvette, when the previous year made more power. On top of that, it only cost GM 100,000 to retrofit all the LT4 motors with their modifications to be built, compared to the millions in R&D for the LS, which at the time made the "same" power.
I am building a 1995 6-speed LT-1 convertible, have removed the opti spark replaced with Torqhead system with newer Ecm, added AR long tube headers without cats, removed smog pump EGR valve 0:30 and will be removing A/C as well, will see how these mods work on my 40k original mile vert, interested in any parts let me know, transformation was motivated by high/low resolution signal failure from the opti or Ecm, Which is why I chose Torqhead, The Chevy dealership told me changing the opti might not fix the problem if the problem is the Ecm, So Torqhead addresses both the Ecm and opti. Antique 30yo car with 40k original miles, individual coil packs and the HPTuner MVI 3 to program the newer obd2 computer.
Hey Lyle. I am looking for a 96 with an LT4 and the manual transmission. Would you like me to call the shop? How soon will you all get it ready for sale?
I'm having an LT4 rebuilt and I'm wondering because they said my cam was wiped out they said all they can put in is a stock cam these things come with the stock can the LT4 from the factory
I got lucky one year at a Mecum auction and stole a 96 Collector's Edition LT4. Took it to the Texas mile, and it pulled off a 154 first run. Surprised me. Then an exfreind made a run the next morning. Left on cold oil and spun rod number 5 or 7. Can't remember which one. P.S. I'm still looking for a good uncut stock LT4 crankshaft. Let me k it if you have one or know of someone who does.
Any idea why there was such a large variance in power? Makes me wonder if testing equipment lost calibration. Has the LS1 been tested to see if it has the same variance?
There wasn't any additional info provided by the Speed shop that did the testing regarding why they thought this variance existed, but all engines vary in actual output from one to the next. I think it seems magnified with the LT4 because I suspect GM "dumbed down" the numbers to make the LS1 look better in the new car. Lyle
@@lyleaulwurm9486 Thanks Lyle. Yeah, I wouldn't expect engines to be exact, it just seems a 50hp variance is excessive. Maybe it was how the engines were broke in or maybe some inadvertently (or intentionally) got a little advanced valve timing from the factory. I think it would be interesting to know if the LS1's varied as much. I had a red on red LT4 coupe with Z51 that I loved and wish I could have kept, really miss it.
Tim bucket, I just purchased a red on red 96 LT4 with the Z51 package in Oct 2023. I was told that this setup was available on less than 100. Love the car.
@@EVLVET Congrats Robert, that just might be my old car! I guess there's a 1% chance! I loved the one I had and hated to sell it, but had to out of necessity. Have fun!
I have this engine in a 1994 z 28 with a procharger .Great engine but it has a major flaw . When run at speeds of over 185 miles /hour for long periods of time it has a tendency to over heat.I guess nothing is perfect.
Although a small percentage of the LT4's may have been able to outrun the Lotus designed/Mercury produced LT5, you can bet the farm that NO LT4 is going to run flat out for as long as the LT5 can. Because back when GM owned Lotus, the Chevy brass demanded that during development, Lotus place a number of the LT5 engines on a dyno and run them from peak torque all the way to redline, back down to peak torque and back up to redline, over & over & over again, for 200 HOURS NON-STOP. The LT5 had to survive these insanely abusive testing hours and still live, which they did. It is for this very reason plus the fact that Mercruiser ( Mercury Marine ) was able to mass produce such complex aluminum castings and keep the close tolerances that Lotus designed into the LT5, that Chevy engineers went after breaking the 24 hr and 5,000 mile high speed endurance records with total confidence. This was done in back in 1990, and those records still stand to this very day. The LT5 that was used to break these records was donated and was actually a reject by Mercury, who told Tommy Morrison and his team that the engine ran well, but had a balancing issue. Morrison's team found the problem and corrected it. ( I don't know what the specific problem was. ) This LT5 engine was bone stock except for headers and open exhaust being used to break of those records.
2 years ago I owned a 50k mile 96 LT4 Convertible I sold for a 70k mile 00 automatic Z51 convertible...even tuned up the LT4 was not NEAR as quick as the 00 so it was probably a 345 horsepower car not one of those 390 horsepower cars...
I would assume that they were car dyno numbers that accounted for the roughly 15% power loss running through the drivetrain...which would put your car at 365.7 horses at the flywheel. Lyle
how could there be such a disparity in the LT4 engine 330 to 391? thats a 61hp range with the same exact components?? How can that be? What was different about the LT4 that made 391 vs the 330 ones?
I have a 9c1 Caprice with an Lt4 motor the top speed I've gone on hardy toll way was 168 a 2019 impala kept testing me never saw him again 😂😂 I slowed down because the exit was coming in fast and I didn't wanna shit on my brakes also my a/c clutch fell off 😭😂
I don't get it. How can there be such a huge variation in the LT4 HP/Torque if they are all built the same? That doesn't make sense. provided they were all built the same?
You are right. if there would be a difference of 10HP between the Engines you could say "Thats are the Producing Tollerances" But 50HP differences ??? Thats not possible.
Look at the percentages I quoted from verified testing: 75% of LT4's made 345hp or more. Only 27% of those made more than 359hp, so take your 10-12 hp variation and add the 15 hp that GM sand-bagged in their numbers and you end up with a representative median that clearly indicates that the LT4 was designed and built to make around 350hp. Lyle
My thing also is, what in the world could be different in a 330hp vs 400hp LT4 car? They had exact same cams, intakes, etc. I mean some could of had a hotter tune from the factory but not 60hp worth. It would of had to have a completely different camshaft or heads to make 65+ more HP.
Notice that only a very low percentage of these engines made less than 345hp...I think it had less to do with wildly varying performance and more to do with GM manipulating the numbers to make the new LS1 look better at 345hp. Lyle
Enjoyed this presentation Lyle. BTW, your welcome to forward information to me about this particular 96' C&S has. I might be interested. I'll leave you a message via phone also. Thanks.
@@lyleaulwurm9486 1 minute the car starts and runs just fine and the next it starts and dies 2 or 3 seconds later. I checked the fuel pressure and it has 35 before its starts and after it dies
My Dream Car was always a Black LT4. But sadly i live in Germany. And in Germany an LT4 Corvette is more Rare than a Ferrari F40. No really, i make no Jokes. Im pretty sure there are more F40 than LT4 Corvettes here. So i swiched to a C5.
Gotta' disagree with 'some LT-4's out-ran LT-5 '. Even '90 LT-5 , with restrictive exhaust , would exceed LT-4 . I am 'Schrade' . Google Schrade + corvette . Last count , in '16 , after selling Z , and 3 C4 resto's , web video / photo doc'ed resto's were near 675k web-hits . Including endorsement by Jerry Downing of LT-5 development team , of my induction system resto (got screenshot) .
LT5 made more power for sure but it also added a lot of weight. The fast LT4's wouldn't be far behind and handled better for sure. The ZR-1's had crap suspensions, didn't have the heavy duty springs and bars.
The weirdest thing of all was 1 year only. Doesn’t make any sense. All the development, EPA certification costs, testing costs, etc for 1 year? That’s not how manufacturers do things. Add to that the LS1 was coming the next year. So they had two new Corvette engines being developed at the same time bascially. Again makes no sense. We never see the LT4 again. Again makes no sense.
Austin, my best guess is that the LT4 had been in development for a long time before the LS1, and that it was going to be the "swan song" engine of the last Corvette production year. Then, John Cafaro and some other really committed guys came up with a new Corvette at a price that the bean-counters couldn't say not to, and the LT4 became the hot engine option after the LT5 was discontinued and they wanted something special for 1996. That way, the expense of making the LT4 could be at least justified (in part) on paper. Again, just a guess. :) Lyle
The LT4 was built that way because the Vette engine team got pissed off at the very idea of the LT5 not being a Chevy built engine. This was their way of giving Dave McClellan the finger: “See, we could have build that ZR1 engine if you’d let us!”
Dave McClellan had nothing to do with the LT5 . He was Corvette Chief engineer from 75 to early 90's . Graham Behan of Lotus worked on the LT5 . Graham and the Lotus team were busy working on a 475 h.p. second gen LT5 for the new Corvette when the LT5 was canceled in 1993 . Yes way back in 93 . Chevrolet engine team was already working on the LS series of engines when the LT5 was terminated. So the remaining LT5's were used up in the following 93 , 94 , and 95 ZR1'S. McClellan likes to give himself credit where none is due when it comes to the ZR1 power train .
I have read something like that too.
I knew it! I had a 1996 LT1 Corvette and now own a 1996 LT4 Corvette. I kept saying
that the LT4 had more like 370 hp rather than the 330 hp rating the factory had... it was
much faster than the LT1. Awesome to know... thanks Lyle.
My first new car I bought was a 1996 Z28 with the LT-1 rated at 285hp and a 6-speed manual. I remember seeing a Grand Sport Corvette on the showroom floor at the time. I told myself that I was eventually going to own a LT-4 Corvette in my lifetime but I couldn’t afford one at the time and my Z-28 stickered at $28,502 when a base Corvette was over $40,000. I was finally able to afford a 1996 base Corvette in Torch Red with an LT-4 and 6-speed manual in 2016 with 18,000 original miles. The LT-4 is insanely faster than the LT-1 in my Z-28. It’s almost like they’re not even remotely the same engine. I understand the 1996 Corvette automatic LT-1 is rated at 300hp but there is something special about the LT-4.
I’m happy to see this video. 20-ish years ago I had both a ‘96 CE LT4 and a 99 6-SPD coupe. I ALWAYS felt like my C4 was quicker but never saw any data to confirm that.
Same here. My uncle had a 96 lt4 and raced a 98 c5 6sp and I was positive the c5 would win, but the c4 was faster. This explains why.
Interesting find isn’t it? 😂
It’s been a theory that GM downplayed the LT4 to not hurt upcoming LS1 sales, like they did for the LS Fbodies.
Does a lt4 have opti- spark how much is your LT4 going for?
@@user-rh5zt7zn2x Yes, it has opti.
Hi Lyle enjoyed this video and you explaining the LT-4 and some LS-1. Have a great weekend my friend.
GM did that withe the Buick Grand National as well! Great video, I learned something new!
I just bought a torch red LT4 out of Arizona with 25,000 miles. It’s gorgeous and awesome.
Curious how much you paid? Look at an lt4 w 29k
I purchased a torch red LT4 last year with only 19K miles for $25K. A garage Queen in pure stock form. No mods except for window tinting as I live in Arizona. This car is quick but not up to par with today’s vets but definitely capable of staying or even out performing a stock C5.
I’ve got a C4 Grand Sport with the LT4 and definitely learned a few things from this video, thank you Lyle! Always suspected the factory rating was low on these engines.
The Grand Sport in 1996 is 100% a an appearance package. That's it. You could get a "Base" or "Vert" 96 Corvette with the same options as the Grand Sport with the exception of the hideous Pep Boys rear wheel flairs the GC Coupes had. Thankfully, these days you can buy A-Molds that will fit a 315 tire and tuck under the stock fenders. That said, when these cars were new in 1996 we called the LT-4 Cars "Grand Sports". Got completely smoked by a C4 back in 1996-7? It was likely a "Grand Sport" as the saying went. I remember rolling in my buddies dad's Turbo Supra and a White Vette with brand new tags came up next to us at a light. As it pulled away his dad said "Must be one of them new Grand Sport cars".
Hell, even the model kits of the day reflect this.
I have a Comp Yellow 96 with 14k miles on the clock in the garage. It's a hoot.
Great Video!
My LT4 quit working. No signal to the optispark. So now she sits in storage waiting to go to a resto shop. She sure was fun.
Interesting, my son, in his 96 Collectors Edition, posted faster lap times at the National Corvette Museum race track, than I did in my LT4.
Another interesting fact. When Museum archive sent me the build sheet and window sticker for the LT4, I noticed that car started its life 11 hours earlier than my son!
I gave the car to him when he graduated from OSU.
How cool to have a Corvette built on your actual birthday!!!
I bought a used LT4 Torch Red convertible a while back. The previous owner, who was a moderator on the Corvette Forum, bought it back from me a year later. That was a sweet car. Gordon Killebrew looked it over at a clinic he held and pronounced it "a garage kept car". He was impressed.
I met Gorden before he retired. He worked at the Corvette Assembly Plant in Bowling Green. A very fine man indeed.
I'm so happy the LT-4 only came with a manual.
Thanks for making the video and answering the question, Lyle! It was great! I’m going to search for more info on those LT4 results, so interesting!
Great video! Thank you for the info!
I have heard this before, but thanks for verifying the HP possibilities of the LT4
Great video. Just as this video came out, I purchased a torch red 96 LT4 out of Arizona with only 25,034 miles. It was in a Texas garage, then in a North Carolina garage, then in an Arizona garage before being shipped to my garage. My car is close if not as fast as a 90 zr1. If you can find one in excellent condition under$18,000, you will have a great performance car for the money.
I'm lucky enough to own an LT4 Collector Edition coupe. One of the surprising things about my car, which is admittedly a little on the tired side, was the performance of it on a long country drive organized by a late Corvette friend of mine. He had a Commemorative Edition Z06 which I believe had a few simple bolt ons but wasn't heavily breathed on. Near the end of that drive we got onto a 4 lane divided highway, and bearing in mind we're running with 3 Vipers we got going quite quickly. Between 100-130 my car had no trouble matching pace with his Z06. Now that wasn't a scientific test or even a proper roll race, but when he stood on it, I could keep my car in 4th and keep up with no issues. The high speed performance of this car has really, really impressed me, and while it still needs some TLC (vacuum leak, I believe) I find it very easy to believe that it's still putting out more power than the rated 330 hp. Now with that said, the car now has about 85k miles, and while I did take it to the drag strip I'm just too afraid of destroying the clutch to launch it really hard, and having never run at a drag strip before my times sucked. On the open road, though, this car rips. I would upgrade the brakes before adding power.
A year of LT4 ownership convinced me to buy an MX-5 RF. I love the targa way more than I thought but it's just too fast for me as a daily. Besides, it's a special car and I want to keep it that way.
EDIT - My neighbor picked up a 2007 C6 with a 6 speed this week. Went for a drive with him today and there's very little difference between the two (less than half a car length) from 70-125 in fourth gear in each but I don't know how the gearing compares.
I'm in process of completing a LT4 swap into 72 C3. Have 4L60e attached to it with modified PCM. Close to fire up. Thank you for this video.....
Always interesting tid bits of info on these engines!!
Shhh! Your giving away all the secrets! I worked for a Chevy dealer in '96 as a salesman with another guy who was also a gearhead like me. We were checking out the specs on the LT4 and researched as much as we could since it was so interesting. (You forgot to mention the sodium filled exhaust valves) We both came to the conclusion that Chevrolet was sand bagging on the horsepower! I often wondered how it would perform with a slightly lower rear end gear to take advantage of the high rpm capabilities. I bet it could be a real beast on the drag strip that way. Unfortunately it was a small dealership and we never saw one.
I work as gm tech back in the day, l saw a lot of LTl intake gaskets on LT4'S right from the factory.
Thank you Thank you! I have the LT4 in a collectors edition and LOVE it! IThank you for this video. I installed new tires and am going to dyno mine soon I will update with RWHP from Kelly Moss Racnig .
Enjoyed this! An engine series would be cool. You should cover the L88 and ZL1 engines! The 2nd and only ZL1 Convertible sold a while back for about 3 mil!
My budgeted journey 2 years ago to attain a dream car from one of many posters in my room when i was 15 in the 90s led me to the C4. I wanted a stick and i wanted the best version of it. (ZR1 outside of budget)... conclusion = LT4. One day just happened to ride by a mechanic shop out of town on the way to a job and saw a torch red C4 parked outside that had some kind of marking on the right side of the back bumper. It didn't have any sale sign but i called anyway and yada yada, 2 weeks later its in my garage. Love my LT4. The whole story around the LT4 makes it even better.
Lyle, your level of knowledge is incredible. Thank you.
Once again Lyle, a very, very informative video. I love your in-depth analysis of the LT4 engine. I had no idea that they had roller rockers. Obviously the LT4 was real turning point for GM as to what was coming down the road. Well done Lyle. 👍👍 Save the Wave 🙋♂
Alot of the tech of the Lt4, went into the LS1 and LS6 . Also if you can't find a Lt4 engine Corvette. GM saved same Lt4 engines for the 1997 Pontiac Firehawk, and the 1997 Camaro SLP SS.
I got my lT 4 new in Dec 1995. And I am not going to sell it
I love that car. it is a convertible with factory hard top.
Great info. Thank you.
Wau, those 390 hp LT4 were closing to LS6 from Z06...
Awesome video Lyle. Bought my torch red 96 Lt4 a few years ago and still have it. Don't drive it much as I'm getting older and these cars are not user friendly when it comes to getting in and out of them. Do love the power and changing the gears when I do drive it. Thanks again for the info.
Great video, thank you! I have also read that GM held focus groups to decide whether to go with an overhead cam multi valve for the upcoming C5. People preferred the power delivery of the pushrod motor, just wanted more without sacrificing low end power.
Great video Lyle. I love when GM does this. Like getting the good gift in a grab bag. The way they made the 82 with the same drivetrain as the next generation, I wish the Crossfire would have worked out for them. It was exciting as a child the way they marketed these things in the 80's. I thought they should have made all 04 manuals with a Ls6. But we got the Top mount battery cables, and faulty gas tank crossover...no love loss for the C5 despite that. I believe there are no bad Corvettes, but my strongest desire is for the final year of each generation, especially the 1996/LT4 6spd.
Jesus will never stop loving you
Good video! I have a stock LT1 automatic with a 3.54 rear differential, that is seat of the pants.
All your videos are great!
Thanks for this info Lyle. Way way too many upgrades for a mere 30 HP, had a feeling would be what you spoke.
The LT4 really is special. To be fair though, the LT1 made well over 330 on the engine Dyno, in fact 330 is a lower number for a later healthy stock LT1.
Thanks for the great info. I have a 96 collector's edition. Took her to the texas mile back in 16. Managed to get a 154 and a 156 mph in a mile. Then let a freind drive her and on his second run spun a rod bearing for me. Fast forward to 2 weeks ago and I have finally found a stock crankshaft. Now I can start the rebuild. Yea
Excellent video great information.
Hello all. Hey what a great video. Thank you for making such an honest detailed aldescription of the lt4. I own a 96 white with red low mileage lt4. And an 08 ls3 Jetstream blue. Of course I love them both but the c4 is still funner to drive overall and especially at slower speeds. It just feels like a ton of torque. Radiates thru you Wraps itself on and around you I love the sound too. Like a jet engine lt4 owners know what I'm talking about . I'm virtually bone stock with upgraded plugs. Wires air intake . I'm 56 owned and drove a lot in my life this car is truly spectacular. I had it dynoed last year 3 x and it came out between 402 and 410 hp. And it feels like it. Head to toe.
It feels. Feels. Like it has more torque below 2000 rpm then my C6. But my ls3 takes off like a rocket and is faster. Overall. Brutal after 5 k rpm. Lt4 underated yes. In all areas. Great video .
I did a lot of research before deciding to purchase my C4 Gen '96. I knew after reading all the articles and comments from others this was a special hidden gem! Thanks for confirming 👍 I own a '96 Collector Edition with just a little over 89k. Am I happy? What do you think 😊 Great info and thanks.
I don’t doubt your conclusions or the facts that you cite. Another great video, and thank you. What is baffling is not that these engines made more HP than advertised. What’s baffling is why there was such a dramatic disparity among LT4’s (330 to 390?!?) What accounts for this?
Nice video thanks for info!
I do believe the differences in HP numbers. I’ve owned about 15 LT4s over the years and there were a couple that just felt faster. Like ZR1 fast. Hard to believe factory didn’t have better control of that but I’m not complaining.
Always suspected this. The LT4s ran almost as hard as the ZR1s. A HOT CAM and headers puts it right there with the ZR1.
Great CZcams as always Lyle, im pretty sure that the C4LT5 was also underrated, bring on your stock LT4 Vette, the Zr1 will kill it anyway you want to run...
Again, keep up the Great channel, you are the vette man
Too bad your lt5 isn't even a Chevy motor
Thanks for the video! In your opinion, what performance upgrades would you recommend for a LT4 if any? Thanks
Have been wanting to get my hands on a 96 LT4 for a couple years now. This just made the “want” a need 😂
Are you going to make Lyle and offer? 🤔
@@WarriorsPhoto nah but if it was polo green 👀 I’d have to make a very responsibly irresponsible decision 😎 lol
@@marcust510 😂
Same here but with different colors though.
@@WarriorsPhoto what color would you prefer? Lol
@@marcust510 RED. Absolutely I'd get a C4 Corvette in red. (:
My son has a '96 Collector LT4. Nice car, opti spark is a nightmare. Great info, thanks.
My 96 LT4 with 111000 miles still has it's original dis. You have to keep them dry.
Torqhead can solve the opti nightmare. I spent 2400 but never regretted it. Also gives you a tunable computer.
I've been eyeing Corvettes for a few months and hope to make a purchase soon. I'm torn between a 96 LT4 or an 02-04 Z06. There is also a 92 ZR1, but not sure I want to potentially daily one. I know the Z06 is faster and has more room, which is a plus since I'm 6'1" 260lbs. However, the silver 96 with red and black interior is gorgeous! Tough call.
I have a 96 LT4, Z06 is a much better car. The chassis alone is words apart.
Yeah my name is Brandon I have a 96 convert LT4 that I just had rebuilt by machine shop and I was running it with my friends 02 convert with the LS1 and I did beat him just barely a few times in a row and he agreed that my car was faster than his kind of blew our minds but love the car it also came with the CC 2 option so with the LT 4 and the CC 2 I believe it's a pretty rare car
To LT4s were meant to rev They just picked the lower RPM number to get the 3:30 It had a lighter weight valve train and crankshaft The thing would spin
I've own one for 9 years the lt4 have rocker 1.6 instead of 1.5 with taller valve cover and a cut-off at 6400 rpm done hot cam from performance part shorty header and a good aftermarket clutch with steel flywheel dam this car miss me soo munch!!! the third and fourth speed was a blast!!! lost 1 time and almost a second time my driving liscence cant keep that thing ....
Lyle I injoy your videos and I am not a vet owner but will be looking for a 96 lt4 , please let me know your price range when you're thrue with the one your working on. Ps I am retired , looking to drive cross country!
I find my LT4 much more fun to drive than the 3 base C5s I’ve had. 😊
Are there manufacturing dates or vin numbers on the engines of the lt4 that correspond with the higher horsepower versions? Is there a way to tell what you might have without actually going to the dyno?
No, there isn't. A Dyno is the only way to know for sure. :) Lyle
Love my 96 ce vette 6spd LT4
Lyle, great video on the LT4 engines....an LT4 out running a LT5 ZR1? eh, I don't know about that
The LT5 added a lot of weight.
I have one and completely agree
Wow, I've watched a lot of Videos on LT4 cars but that's a hell of a lot more info than I've found out before! I missed out on one before finding my C5. What's the weight difference between a C4 LT4 and a normal manual C5?
The ZF 6 speed is a lot heavier transmission than the TF56. A 96 coupe weight 3307 and C5 coupe weighs 3247, so not a whole lot of weight differences.
Bought a 96 LT4 used in 98 with 24k miles I think and at 55k miles 1 roller lifter had some tiny chunks of metal come out of the roller and take out 2 cam lobes. Very disappointing, especially the dealer and GM's response which was too old, too many miles, sorry, nothing we can do. Had it fixed on my own and ended up selling it in 2004 for a reason that never materialize...so should have kept it. Anyone else hear of any roller lifter issues? "Rumor" back then was that the cam and lifters were Comp Cams.
As an LT4 owner I appreciated this video! Do you have any theories on why there was so much VARIANCE between the LT4 engines that were tested? I realize that manufacturing tolerances can make some engines make more power than others, but a 70 hp difference seems MASSIVE for the same engine design!
That’s s great question
I would like to know that too.
I’m kinda thinking 400hp out only them is hard to believe. 360hp is one thing. I mean did they do percentage estimates or actually pull the motor and do at engine power tests? 🤷♂️
Remember that engine dyno was not what it is today we now know dyno differences and more people have them
@@utahcountypicazospage5412 How do you think the test would go if done today?
Well, here I go again: In 1995 I acquired 2 LT1'S. Testing and 1 to keep. Blue and a Black. bot autos both 2:59 rears. The blue was a real bow wow. The black/red was and became a bigger beast. Still have it actually. Bone stock the black/red ran consistent 13:38’s @ 104 mph. Best time ever was 13:10 at 110mph. Month of December. I did use a hypertech programmer. Red line was 6300. Track was Capital Raceway, Crofton, MD. Little C4 was knocking down big C4’s with 383’s. One ran 13.6’s @ 110. My clock was faster, but their mph was faster. Who won? Of course, the quicker clock in this case. My first adventure into 383’s, a short stroke unit. 5.56 I beam rods, with hypereutectic pistons got me to 400 hp and 466 lb trq. Still being hungry I got a 97 Camaro Z LT1 and built a long stroke 383/388. Not sure because Probe Industries and Vigilante Racing have different numbers for the same config. This one made 530 hp and with some unique additions; namely individual coil packs; and specialty plugs from NGK i estimate it at 560 hp. Heads are Trick Flow 185; given the smokey bear treatment, up to 2:08 titanium valves. Build and dyno can be seen here. paceage.com/a-383-388-c4-lt1-560-hp/
Engine still has 0 miles since being finished some years ago. Guess I need to sell; but promised never. Travel bug got me. Loss interest. Hate that. Torque converter is Yank SS3600. Swapped out Dana 36 for 44 with 3:42. Set car up hoping for 1 to 1100 or so STS hp. A known builder doing my research told me they have a club of 1000 hp C4's; one or 2 in the 1100 hp ranges. I have had at least one C5's but still love my C4's. One more thing. If you want to hear what the engine sounds like in car. go here; www.ghostcopstv.com/ There are 2 trailers there.
I was in the Virginia Beach area; came to Florida for a visit and wanted to come back. Actually I landed in Sarasota; in July.
Believe it or not; I have been by C & S, without even knowing they were there. Today in part. So I get on YT and without knowing how; there is this cool guy talking 1996 LT4’s.
Hope to get by C&S soon. Thanks all.
Did GM ever offer an explanation as to why the LT4 had such a great of horsepower variation on engines that should be very close to being the same ? Are there any LS1s with that 345-350 plus almost 50 hp more that exist. Those greater hp engines were not by accident in the LT4s.
They did make a Silver Grand Sport ( Collectors Edition) with 6 Speed , LT4 Aluminum Heads 330 HP and 340 t ft and it also had Silver Painted Grand Sport Wheels not of chrome
The Collector's Edition and Grand Sport were separate options. Both could be had with the LT4, but the CE did not have the wider rear wheels of the Grand Sport Coupe. The CE car was a paint and appearance package for the most part, with the satin ZR-1 style wheels added. The Grand Sport was a limited production model, while the CE was not. Similar, but different. Lyle
I had two 96 Lt4 cars. A black 96 Lt4, and a 96 Grand Sport #901. Really enjoyed them both.
Do you have the Grand Sport?
@@WarriorsPhoto , I sold 901 back to buy a vette in 2018. They sold it to a guy in Gainesville, Texas. I had a 77 L82, 96 Lt4, 2000 hardtop, and 96 Grand Sport. I now have a 2019 Mustang GT.
@@markbaumgartner7261 Keeping American 🇺🇸 and V8. (:
What was your favorite?
@@WarriorsPhoto, the 2000 FRC, because that is what Chevy used to make the C5 Zo6 the next year. It was lighter than the C5 coupe, and handled the best. I liked the Grand Sport but was afraid of someone hitting it!
@@markbaumgartner7261 I feel the same way about the C5 FRC.
It was lightweight and handled well. It also felt peppier since the car lost some weight over a standard C5. It helped show how good 350 HP was on the road.
Do you regret getting rid of it?
Hey buddy great video as always im about to jump back into the market for a 03 04 zo6 , did you do any videos on that gen i remember you saying you own one at the shop. Thanks for any input
I've done several buyer's guides and "what to look for" videos on the C5, 99% of which pertains to the 03/04 Z06. Those are the two best years, and beyond sniffing out whatever mechanical needs a car may have to make it "perfect", they have very few issues. Happy Hunting! Lyle
Great clip!! Orlando here - wish you were closer! How can I find out the "actual" horse power of my Lt4? I have a "Collector Edition" Convertible Lt4 with light gray interior and only 9700 miles. Also have the original Goodyear Eagle GS-C tires!
Only true way to determine actual hp is a dyno run. Lyle
Support
You the man thx for the info #320
Is it the higher revving that gives it a zr1 like performance
I’m lucky enough to have a 96 LT 4 convertible and a 91 ZR-1. Also have a 95 LT1 Firebird . Although the LT 4 definitely feels faster than the LT 1 I don’t think it’s as quick as the ZR-1. A club member who has an LT4 collector edition than replaced it with an 03 LS1 car has said to me that he didn’t think the LS1 was faster, he felt they were similar.
Wow, excellent article. My only question is, if I am shopping for a 1996 Corvette, is there a way to determine if it has one of the more potent LT4 engines?
No, but there is a 75% chance that it will have at least 345 horses according to the study.
Lyle, was the LT4 fuel pump different than the LT1? I've heard this a couple of times, but you didn't mention it in the video. I have a 96 Grand Sport and attempted to replace the fuel pump with a Delco unit from one of the major on-line suppliers. Not only did the replacement pump look different, but it had a ground issue that made the fuel gauge read 'empty' with a half tank of fuel in the tank. I returned it for a replacement and the replacement did the same thing. Resistance was bench checked before installation and it showed a full range of resistance from zero up to around 80-90 ohms, yet when installed, low single digit readings and empty tank at the gauge. When I installed the original pump back it, it correctly indicated the half tank of fuel. Is the LT4 pump a higher flow unit to support the higher flow injectors?
I belive back in 1993 or 1994 the was a Grand Sport "Prototype" advertized. It was Represented to have an "LT4 V8 350 HP". So it was always in the books to be a 350 ish hp motor. But after spending millions developing the new LS platform that was to deliver 345 hp, GM had to under rate the LT4 due to the higher actual HP output. It would have customers questioning whether or not to buy the new corvette, when the previous year made more power. On top of that, it only cost GM 100,000 to retrofit all the LT4 motors with their modifications to be built, compared to the millions in R&D for the LS, which at the time made the "same" power.
You just repeated what Lyle said.
@@nashbridges120 not exactly. He did not mention the prototype GS car. Nor the cost for retrofitting LT4s
I am building a 1995 6-speed LT-1 convertible, have removed the opti spark replaced with Torqhead system with newer Ecm, added AR long tube headers without cats, removed smog pump EGR valve 0:30 and will be removing
A/C as well, will see how these mods work on my 40k original mile vert, interested in any parts let me know, transformation was motivated by high/low resolution signal failure from the opti or Ecm,
Which is why I chose Torqhead,
The Chevy dealership told me changing the opti might not fix the problem if the problem is the Ecm,
So Torqhead addresses both the Ecm and opti.
Antique 30yo car with 40k original miles, individual coil packs and the HPTuner MVI 3 to program the newer obd2 computer.
Hey Lyle.
I am looking for a 96 with an LT4 and the manual transmission.
Would you like me to call the shop?
How soon will you all get it ready for sale?
I'm having an LT4 rebuilt and I'm wondering because they said my cam was wiped out they said all they can put in is a stock cam these things come with the stock can the LT4 from the factory
I got lucky one year at a Mecum auction and stole a 96 Collector's Edition LT4. Took it to the Texas mile, and it pulled off a 154 first run. Surprised me. Then an exfreind made a run the next morning. Left on cold oil and spun rod number 5 or 7. Can't remember which one.
P.S. I'm still looking for a good uncut stock LT4 crankshaft. Let me k it if you have one or know of someone who does.
Any idea why there was such a large variance in power? Makes me wonder if testing equipment lost calibration. Has the LS1 been tested to see if it has the same variance?
Id love to know also. This question has nagged me for 30 good years now.
There wasn't any additional info provided by the Speed shop that did the testing regarding why they thought this variance existed, but all engines vary in actual output from one to the next. I think it seems magnified with the LT4 because I suspect GM "dumbed down" the numbers to make the LS1 look better in the new car. Lyle
@@lyleaulwurm9486 Thanks Lyle. Yeah, I wouldn't expect engines to be exact, it just seems a 50hp variance is excessive. Maybe it was how the engines were broke in or maybe some inadvertently (or intentionally) got a little advanced valve timing from the factory. I think it would be interesting to know if the LS1's varied as much.
I had a red on red LT4 coupe with Z51 that I loved and wish I could have kept, really miss it.
Tim bucket, I just purchased a red on red 96 LT4 with the Z51 package in Oct 2023. I was told that this setup was available on less than 100. Love the car.
@@EVLVET Congrats Robert, that just might be my old car! I guess there's a 1% chance! I loved the one I had and hated to sell it, but had to out of necessity. Have fun!
I have this engine in a 1994 z 28 with a procharger .Great engine but it has a major flaw . When run at speeds of over 185 miles /hour for long periods of time it has a tendency to over heat.I guess nothing is perfect.
very funny?
Although a small percentage of the LT4's may have been able to outrun the Lotus designed/Mercury produced LT5, you can bet the farm that NO LT4 is going to run flat out for as long as the LT5 can. Because back when GM owned Lotus, the Chevy brass demanded that during development, Lotus place a number of the LT5 engines on a dyno and run them from peak torque all the way to redline, back down to peak torque and back up to redline, over & over & over again, for 200 HOURS NON-STOP. The LT5 had to survive these insanely abusive testing hours and still live, which they did. It is for this very reason plus the fact that Mercruiser ( Mercury Marine ) was able to mass produce such complex aluminum castings and keep the close tolerances that Lotus designed into the LT5, that Chevy engineers went after breaking the 24 hr and 5,000 mile high speed endurance records with total confidence. This was done in back in 1990, and those records still stand to this very day. The LT5 that was used to break these records was donated and was actually a reject by Mercury, who told Tommy Morrison and his team that the engine ran well, but had a balancing issue. Morrison's team found the problem and corrected it. ( I don't know what the specific problem was. ) This LT5 engine was bone stock except for headers and open exhaust being used to break of those records.
2 years ago I owned a 50k mile 96 LT4 Convertible I sold for a 70k mile 00 automatic Z51 convertible...even tuned up the LT4 was not NEAR as quick as the 00 so it was probably a 345 horsepower car not one of those 390 horsepower cars...
Are these true engine dyno numbers or car dyno. My CE dyno was 318 hp. How would that equate to engine bench numbers?
I would assume that they were car dyno numbers that accounted for the roughly 15% power loss running through the drivetrain...which would put your car at 365.7 horses at the flywheel. Lyle
Hi Lyle IM interested in the 96 lt4 manual .What kinda money is it going for an when will it be for sale Thanks craig
First! thanks for a very interesting video
how could there be such a disparity in the LT4 engine 330 to 391? thats a 61hp range with the same exact components?? How can that be? What was different about the LT4 that made 391 vs the 330 ones?
I have a 9c1 Caprice with an Lt4 motor the top speed I've gone on hardy toll way was 168 a 2019 impala kept testing me never saw him again 😂😂 I slowed down because the exit was coming in fast and I didn't wanna shit on my brakes also my
a/c clutch fell off 😭😂
Does anyone on know bout swapping a LT4 in to a 1980 Malibu with an automatic?
im going out to drive my triple black 96 LT4 convertable, its 2:30a.m. I am cool
How do I know if my LT4 is one of the 10% or 15% that made more power?
The only way to know for sure is to have it dynoed. Lyle
If you know the quarter mile time and the car's weight there are calculators that determine horsepower.
Where do you see the prices of these going in the next couple of years? Are they going to be collectible?
The Grand Sport and 96 Collectors edition lt4 cars.
@@markbaumgartner7261 what about the regular ones?
@@trevor1042 , they are worth about $3000 more than a standard LT1 Corvette. But a z51 suspension is worth more than the adjustable shocks.
Kinda hard to believe one was sitting right at 400hp. 70hp over advertised power? I am hoping this is true, but kinda wondering if any LT4 had 395hp.
It was verified in an engine lab, so it had to be close to that number. My guess would be most were sitting at about 360hp. Lyle
Kind of lost me my 2016 Z06 is a LT4 at 650 hp is it a 2nd generation engine ?
Totally understand your confusion....GM Recycled the LT1 and LT4 monikers from the 1992-1996 engines of the same name. Lyle
I don't get it. How can there be such a huge variation in the LT4 HP/Torque if they are all built the same? That doesn't make sense. provided they were all built the same?
You are right. if there would be a difference of 10HP between the Engines you could say
"Thats are the Producing Tollerances"
But 50HP differences ???
Thats not possible.
Look at the percentages I quoted from verified testing: 75% of LT4's made 345hp or more. Only 27% of those made more than 359hp, so take your 10-12 hp variation and add the 15 hp that GM sand-bagged in their numbers and you end up with a representative median that clearly indicates that the LT4 was designed and built to make around 350hp. Lyle
My thing also is, what in the world could be different in a 330hp vs 400hp LT4 car? They had exact same cams, intakes, etc. I mean some could of had a hotter tune from the factory but not 60hp worth. It would of had to have a completely different camshaft or heads to make 65+ more HP.
Notice that only a very low percentage of these engines made less than 345hp...I think it had less to do with wildly varying performance and more to do with GM manipulating the numbers to make the new LS1 look better at 345hp. Lyle
Enjoyed this presentation Lyle. BTW, your welcome to forward information to me about this particular 96' C&S has. I might be interested. I'll leave you a message via phone also. Thanks.
Ship it to the netherlands for me please 😮😊
I have a collectors edition 1996 lt4 that Im having problems with and would really appreciate your help?
What do you have going on? Lyle
@@lyleaulwurm9486 1 minute the car starts and runs just fine and the next it starts and dies 2 or 3 seconds later. I checked the fuel pressure and it has 35 before its starts and after it dies
@@jlindsey7192 May be a VATS problem...clean your pellet in your key (or use a spare key if you have one) and see if it changes things. Lyle
@@lyleaulwurm9486 I was told the car won't even turn over if it's the Vats but I will bypass it under the dash.
@@jlindsey7192 Does it correlate with hot or cold?
My Dream Car was always a Black LT4. But sadly i live in Germany. And in Germany an LT4 Corvette is more Rare than a Ferrari F40. No really, i make no Jokes. Im pretty sure there are more F40 than LT4 Corvettes here.
So i swiched to a C5.
Gotta' disagree with 'some LT-4's out-ran LT-5 '. Even '90 LT-5 , with restrictive exhaust , would exceed LT-4 . I am 'Schrade' . Google Schrade + corvette . Last count , in '16 , after selling Z , and 3 C4 resto's , web video / photo doc'ed resto's were near 675k web-hits . Including endorsement by Jerry Downing of LT-5 development team , of my induction system resto (got screenshot) .
LT5 made more power for sure but it also added a lot of weight. The fast LT4's wouldn't be far behind and handled better for sure. The ZR-1's had crap suspensions, didn't have the heavy duty springs and bars.
Gee, Mr “Google me I’m Shrade +”, you shoulda’ known that!
The weirdest thing of all was 1 year only. Doesn’t make any sense. All the development, EPA certification costs, testing costs, etc for 1 year? That’s not how manufacturers do things. Add to that the LS1 was coming the next year. So they had two new Corvette engines being developed at the same time bascially. Again makes no sense. We never see the LT4 again. Again makes no sense.
Austin, my best guess is that the LT4 had been in development for a long time before the LS1, and that it was going to be the "swan song" engine of the last Corvette production year. Then, John Cafaro and some other really committed guys came up with a new Corvette at a price that the bean-counters couldn't say not to, and the LT4 became the hot engine option after the LT5 was discontinued and they wanted something special for 1996. That way, the expense of making the LT4 could be at least justified (in part) on paper. Again, just a guess. :) Lyle