,,,,,,,,,,,,,,,,,,,,,,,,,A worked Q-jet by a pro builder will be just as good and maybe out perform the holley.......Check out Andy at Unitymotorsportsgarage,,,,,,,He did a dyno test on a 408 sbc , using a worked single plane weiand and a 800 cfm Q-jet.......In the end it was good , and needed to be richer at the secondaries....Nobody had smaller metering rods to continue the flog.......
Pretty cool. I have a Stock LT1 intake on my 355 CSB, in my ‘69 Corvette. The engine is not not built to the extent of your test engine, but it has excellent drivability and good power. I resisted a single plane intake when I was building the engine because I disregarded all the single plane claims.
I found the same results In my '70 Z-28.The factory aluminum manifold was a much better overall manifold over the open plenum manifolds I tried. GM did a great job as their manifold worked best for me on the street... The magazine whores lied to us about open plenum manifolds... No surprise
lol watching Roadkill & seeing this channel pop up. Love your shows & now gonna follow your CZcams channel I've learned some tricks of the trade from yall keep up the great work guys.
This has been a heated topic since the invention of all V block engines,6,8.12. or 16 cylinders. I believe your problems were in the cam,Not a bad cam just not the right cam. I gave up building fast gasoline motors in my late 40's ,30 years ago,but I always found an open plenum helped to balance out everything, from the top of the carb to the top of the piston all pressure was equal,that makes for a smoother running engine,The fact that you had better results when placing the open spacer in proves it . An open plane is the way to go, Also Victor Jr was always a favorite of mine
Yep. In summer, my regular Edelbroken manifold/carb combo would get vapor locked when trying to restart my 350 after going into the gas station or wherever, unless I let it cool off for at least half an hour. So I switched to the Performer airgap manifold, and I never have vaporlock problems now.
So for years you were telling everyone to use a single plane Victor when a dual plane RPM was clearly the best choice....lol Also, you didn't "cut out the plenum divider". You notched it a very specific amount, copying what Edelbrock has done with the RPM AirGap. I'm sure that Edelbrock dynoed the heck out of that RPM AirGap intake to determine exactly how big of a notch was needed in the plenum divider for maximum performance.
I'm on the fence with the Air Gap intake, at least for my engine. They look awesome and I get the theory behind them. And the only reason I have not installed one yet on my 1970 351 Cleveland is because they only have one part number for the 351 Cleveland. It's neither a 2V or 4V intake. But somewhere in the middle. It's supposed to work on either cylinder head. Now at the moment I'm running the Edelbrock Performer 351 2V intake having swapped from the cast iron intake and 2 barrel carburetor. I'm also running the stock H code heads (2V open chamber). I do have a set of 2V closed chamber heads that I have imported from Australia. I'm not too keen on having a larger intake port into a smaller cylinder head intake port. To me, it seems like that is going to cause incoming air to hit the sides of the intake port on the cylinder head and create turbulence. Can anyone confirm or deny this theory of mine? If they do come out with a true 2V version of the Air Gap, you can bet I'll definitely be looking into it.
I would bet the minor difference in the regular vs air gap isn't the fact it's an air gap but the fact it's a newer design which, to me, is obvious from the gap/crossover in the plenum.
I built a 557 BBC for my 1978 Chevy truck and used a performer rpm air gap with a one inch open spacer. I did not dyno the motor but it runs extremely well with a ton of torque. It’s a 10.5 to 1 pump gas motor with performer RPM square port heads. I used a Comp Cams mechanical roller with.622” lift in & ex with 236*in, 243*ex @.050” with 110* cl. I thought about using a single plane manifold but I felt like the dual plane with spacer would work better especially with the weight of the truck.
I know this is a really old video but the only thing that I didn't see or even hear you talk about cuz accelerator pump and ratios those are what get rid of the bar coming out of the hole but that's only if it's a street car because if you're a drag car you're leaving it 48 to 6200 right off the starting line there ain't going to be no bog
Thanks for the video. I've got the Edelbrock RPM paformer intake without the devider and an inch riser with a 4150 Holly. On a 350 4 bolt main. After watching this video I was like nice i have almost that same exact setup. And it starts like a champ. So how much horses did you get out of it?
What gasket do i use for my edelbrock performer on iron eagle heads? there is a gap at the runners. Seems heads were milled before i got them.1970 350cu
smaller ports on RPM Air Gap, chevy already has 215 cc low cfm flow heads , maybe A 185 cc AFR Head with RPM and vic Jr can be compared with same everything else here. a high velocity head and intake then a slower higher rev vic jr since times have changed.
Thank you for the video! I have been trying to find a comparison on a regular performer vs a performer rpm. Mainly about low to mid range on a 383 chevrolet. Would anyone have any one have any insight on this?
Driveablility and response was better with my 300-36 with no notch milled, it was a mistake doing it .WOT and st driving are two different things. Sucks Holley stopped making it, one of thier best manifolds they made.
You've built a really good long motor with a decent cam head compression setup, but I was disappointed to see you comparing manifolds that were all out of the box... while on one hand is ok, but for the most part doesn't show their potential by not port matching them. That would be a real test. If I was to fill the port up on those heads with epoxy to match the manifold, you'd say I was stupid, obviously killing the flow no end. Not only drastically reducing flow, you're moving the mcsa from the pushrod to the intake manifold.... .6 mach is waiting for you??? Personally I think, that the single plane will be losing more than the dual plane when both are port matched, but I am only guessing.... maybe that's a test for the future. Big "Joe" Sherman said he'd never bolt an intake on without port matching. If I remember rightly when he won the first " Engine Masters" his 360 odd inch motor made over 600hp at 6500 with a mid 230 degree hydraulic roller cam 10:1 comp on the Westech dyno using a single plane Super Victor methinks. Very impressive considering very mild engine. Food for thought for future manifold test comparisons.
With a split plan or an open you have to tune the carburetor situation with a split plan we got a 750 you're only feeding four cylinders with 375 CFMs open problem you're feeding all cylinders with a 750 there's a big difference in fuel atomization with a open problem then there is with a close problem you don't have as much fuel to atomize for each cylinder you need to tune it with your accelerator pumps and pump ratio this is carburetor tuning 101
According to Babvvo and Tebbvo laws, sadly soon all combustion cars and trucks including classics will be banned from public streets in entire EU and Scandinavia :-( In Germany the Green Peoples Party gave order to shorten fuel supply from 2025 on by reducing all conventional fuel stations to only one state operated central gas station per city or county. Car washs will be forbidden too because they are climate killers, now they want to slow down all the gas station pumps from 20 litre per minute to 2 litre per minute...From 2027 on in the EU certain car spare parts will be banned too....as exhaust systems, turbo chargers and even some engine and gearbox oils...California and New York will do the same from 2027 on.... So no investments should be done in oil burning cars any longer....They even created a new kind of crime here, called emissions and smoke crime!!
this is why i have stopped making any further plans on any of my cars it's going to happen, so its not worth spending the amount of $ now, to not being able to utilize what i have or want to have just a risk i am not going to take this is all part of the new world order plan, NOTHING else... regardless of what they say
Wow... antique Engine Masters!
All a bit younger then !
Me too I guess.
I'm sorry, but I wanna see the test with the Q-Jet intake WITH A Q-JET!!!
,,,,,,,,,,,,,,,,,,,,,,,,,A worked Q-jet by a pro builder will be just as good and maybe out perform the holley.......Check out Andy at Unitymotorsportsgarage,,,,,,,He did a dyno test on a 408 sbc , using a worked single plane weiand and a 800 cfm Q-jet.......In the end it was good , and needed to be richer at the secondaries....Nobody had smaller metering rods to continue the flog.......
We used to take the Z28 manifolds and cut them down like that back in the early seventies
Pretty cool. I have a Stock LT1 intake on my 355 CSB, in my ‘69 Corvette. The engine is not not built to the extent of your test engine, but it has excellent drivability and good power. I resisted a single plane intake when I was building the engine because I disregarded all the single plane claims.
I found the same results In my '70 Z-28.The factory aluminum manifold was a much better overall manifold over the open plenum manifolds I tried. GM did a great job as their manifold worked best for me on the street... The magazine whores lied to us about open plenum manifolds... No surprise
Just my favorite girl. Absolutely awesome. U mean milling machine not lathe .
lol watching Roadkill & seeing this channel pop up. Love your shows & now gonna follow your CZcams channel I've learned some tricks of the trade from yall keep up the great work guys.
This is like engine masters before engine masters was even thought of lol
I made my own plywood spacer for my performer rpm. 3/4 inch oak plywood. I just need to cut out that middle divider now.
This has been a heated topic since the invention of all V block engines,6,8.12. or 16 cylinders. I believe your problems were in the cam,Not a bad cam just not the right cam. I gave up building fast gasoline motors in my late 40's ,30 years ago,but I always found an open plenum helped to balance out everything, from the top of the carb to the top of the piston all pressure was equal,that makes for a smoother running engine,The fact that you had better results when placing the open spacer in proves it . An open plane is the way to go, Also Victor Jr was always a favorite of mine
Just a side note,ditch the Holley and run AFB carb
Yep. In summer, my regular Edelbroken manifold/carb combo would get vapor locked when trying to restart my 350 after going into the gas station or wherever, unless I let it cool off for at least half an hour.
So I switched to the Performer airgap manifold, and I never have vaporlock problems now.
They did this same test on Engine Master's years later and the single plane won.
So for years you were telling everyone to use a single plane Victor when a dual plane RPM was clearly the best choice....lol
Also, you didn't "cut out the plenum divider".
You notched it a very specific amount, copying what Edelbrock has done with the RPM AirGap. I'm sure that Edelbrock dynoed the heck out of that RPM AirGap intake to determine exactly how big of a notch was needed in the plenum divider for maximum performance.
I would like to see one of those chinesium eddy rpm airgap copys run back to back with a real eddy rpm air gap...out of the box comparison
Would have like to seen what the Torker II does in comparison.
I'm on the fence with the Air Gap intake, at least for my engine. They look awesome and I get the theory behind them. And the only reason I have not installed one yet on my 1970 351 Cleveland is because they only have one part number for the 351 Cleveland. It's neither a 2V or 4V intake. But somewhere in the middle. It's supposed to work on either cylinder head. Now at the moment I'm running the Edelbrock Performer 351 2V intake having swapped from the cast iron intake and 2 barrel carburetor. I'm also running the stock H code heads (2V open chamber). I do have a set of 2V closed chamber heads that I have imported from Australia. I'm not too keen on having a larger intake port into a smaller cylinder head intake port. To me, it seems like that is going to cause incoming air to hit the sides of the intake port on the cylinder head and create turbulence. Can anyone confirm or deny this theory of mine? If they do come out with a true 2V version of the Air Gap, you can bet I'll definitely be looking into it.
Stay with the performer on the aussie close chamber..heads...my fave street setup..
I would bet the minor difference in the regular vs air gap isn't the fact it's an air gap but the fact it's a newer design which, to me, is obvious from the gap/crossover in the plenum.
I do wonder what influence cam/head combo would have on the effectiveness of the divider notch
Whamo that's 6 horsepower right there everybody, tremendous seat of the pants power!!!
Nice comparo
I built a 557 BBC for my 1978 Chevy truck and used a performer rpm air gap with a one inch open spacer. I did not dyno the motor but it runs extremely well with a ton of torque. It’s a 10.5 to 1 pump gas motor with performer RPM square port heads. I used a Comp Cams mechanical roller with.622” lift in & ex with 236*in, 243*ex @.050” with 110* cl. I thought about using a single plane manifold but I felt like the dual plane with spacer would work better especially with the weight of the truck.
I know this is a really old video but the only thing that I didn't see or even hear you talk about cuz accelerator pump and ratios those are what get rid of the bar coming out of the hole but that's only if it's a street car because if you're a drag car you're leaving it 48 to 6200 right off the starting line there ain't going to be no bog
You should have flipped the pistons around. It’s worth 100 HP!
@@Knucklehead4400 it’s a joke Bro
Thanks for the video.
I've got the Edelbrock RPM paformer intake without the devider and an inch riser with a 4150 Holly. On a 350 4 bolt main. After watching this video I was like nice i have almost that same exact setup. And it starts like a champ.
So how much horses did you get out of it?
Pre-engine masters
What if you milled out an air gap on the regular Edelbrock performer intake manifold?
What gasket do i use for my edelbrock performer on iron eagle heads? there is a gap at the runners. Seems heads were milled before i got them.1970 350cu
smaller ports on RPM Air Gap, chevy already has 215 cc low cfm flow heads , maybe A 185 cc AFR Head with RPM and vic Jr can be compared with same everything else here. a high velocity head and intake then a slower higher rev vic jr since times have changed.
Thank you for the video! I have been trying to find a comparison on a regular performer vs a performer rpm. Mainly about low to mid range on a 383 chevrolet. Would anyone have any one have any insight on this?
Performer about same as stock... weaker than stock on Pontiacs... go Performer RPM/AirGap...
Chevy V8 came stock with air gap 1916 - 1918... LOL!
Is the regular rpm lower (for hood clearance) than the rpm air gap?
Does anyone know the specs where I can mill out the standard performer… I have a mill at my work I just don’t know how much to take off
My God you look young in this video
Driveablility and response was better with my 300-36 with no notch milled, it was a mistake doing it .WOT and st driving are two different things. Sucks Holley stopped making it, one of thier best manifolds they made.
Got my intake chucked up in my lathe. Should i use HSS or carbide? :D
Even Asian cutters work for aluminum...
Lol so the rpm air gap with 1 inch spacer makes the most power torque? Not the performer rpm air gap right lol
How far did you machine the plenum down please?
Chevrolet Power Manual said 3/4 of an inch back in the day. It works good I've done a couple.
Fred Durst
Wow! How did teen Freiberger end up in my feed?
Steve Brule with dark hair...
I'm sorry me being a machinist lol that's a lathe lol that's a mill
lol, even my mum knows the difference between a lathe and a mill
Why they don't come from the factory with the plenum milled ?
cause it doesnt always help. Went backwards doing mine
You've built a really good long motor with a decent cam head compression setup, but I was disappointed to see you comparing manifolds that were all out of the box... while on one hand is ok, but for the most part doesn't show their potential by not port matching them. That would be a real test. If I was to fill the port up on those heads with epoxy to match the manifold, you'd say I was stupid, obviously killing the flow no end.
Not only drastically reducing flow, you're moving the mcsa from the pushrod to the intake manifold....
.6 mach is waiting for you???
Personally I think, that the single plane will be losing more than the dual plane when both are port matched, but I am only guessing.... maybe that's a test for the future.
Big "Joe" Sherman said he'd never bolt an intake on without port matching.
If I remember rightly when he won the first " Engine Masters" his 360 odd inch motor made over 600hp at 6500 with a mid 230 degree hydraulic roller cam 10:1 comp on the Westech dyno using a single plane Super Victor methinks. Very impressive considering very mild engine.
Food for thought for future manifold test comparisons.
With a split plan or an open you have to tune the carburetor situation with a split plan we got a 750 you're only feeding four cylinders with 375 CFMs open problem you're feeding all cylinders with a 750 there's a big difference in fuel atomization with a open problem then there is with a close problem you don't have as much fuel to atomize for each cylinder you need to tune it with your accelerator pumps and pump ratio this is carburetor tuning 101
Your problem was the plenum.
But who wants to look stock?
i wish i would have milled my intake like that. i had same issues on bottom end with my duel plane czcams.com/video/5IVu9tu9UCI/video.html
Walk
According to Babvvo and Tebbvo laws, sadly soon all combustion cars and trucks including classics will be banned from public streets in entire EU and Scandinavia :-(
In Germany the Green Peoples Party gave order to shorten fuel supply from 2025
on by reducing all conventional fuel stations to only one state operated central gas station per city or county. Car washs will be forbidden too because they are climate killers, now they want to slow down all the gas station pumps from 20 litre per minute to 2 litre per minute...From 2027 on in the EU certain car spare parts will be banned too....as exhaust systems, turbo chargers and even some engine and gearbox oils...California and New York will do the same from 2027 on.... So no investments should be done in oil burning cars any longer....They even created a new kind of crime here, called emissions and smoke crime!!
this is why i have stopped making any further plans on any of my cars
it's going to happen, so its not worth spending the amount of $ now, to not being able to utilize what i have or want to have
just a risk i am not going to take
this is all part of the new world order plan, NOTHING else... regardless of what they say
Junk it😅