WHAT MAKES A GOOD NORMALLY ASPIRATED PISTON?
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- čas přidán 12. 05. 2022
- I SPECIFICALLY POINT OUT RING PLACEMENT AND THE DISTANCE FROM THE TOP OF THE PISTON THAT MAKES IT A DEDICATED NA DESIGN!
YOU WILL NOT BE SUCCESSFUL IF THE RING POSTION IS TOO LOW AND IT WORKS BEST ONLY FOR BOOSTED OR NITROUS ENGINES.
KEY INFORMATION IS THE ABSENSE OF CREVICE LOSSES!
COVER PICTURE IS THE RACECAR OF MICHAEL CHRISTIANSON FROM SAN DIMAS, CA. IT IS A 4.170 STROKE 351W WITH NEW DESIGN TFS TWISTED WEDGE HEADS. PUMP GAS WILL RUN IN THE 9 SEC. 1/4 MILE!
Obtw, I get numerous requests for technical advice and if interested, tex me @ 626 203 2712. Half hour to 1 hour+ rates are available. Most calls go over as posted and it is ok. US Pacific time zone.
Thanks Ben
Great info that's not readily discussed. I too have damaged pistons moving the ring pack up too high for the heat levels.
Agree and if you are brave to hold it higher it is best with superior coatings and it helps but a soon as it detonates some of the coating flake off and you are back to square one.
I always learn something from your videos . I can’t thank you enough for sharing your extensive knowledge on engines …
Love your valuable information.
Thanks for watching!
The Crankshaft behind you is for an FE Motor. 👍💙
Yes sir! lol
Thanks for video!
Thanks for supporting my channel.
Great info as always! I’ve mentioned an old sbf stroker n/a engine I built years ago that ran really good back in the day!
I remember the ring pack being much closer to the top of the piston than a stock piston! Never really thought about it much but after watching your video it all makes sense! For a short minute I was the talk of the drag strip of how good that motor ran for what it was! Probably more factors involved than just the ring pack positioning , but it all worked together to perform better than expected!
Mark, thanks for your input. Among other things a ring pack plays into the more power scenario more than most people realize. You did and that gave you a hint of not taking these things for granted.
Thank you Ben.
More great stuff to learn on this video.
These things are sometimes overlooked .
Explanation of this is very interesting . Love it.
Thanks George and long time no see bud!
Thankyou mr alameda for sharing your experience.wow engine's are a list of variables so fascinating in there complexity love it.peace
Thanks for supporting my channel!
Professor Ben:)
I had a set of trick flow twisted wedge heads , flat top Pistons, mild cam, I think it was what the 88 formula firebird I had it in,. Should have Had stock, I ported the tpi, and matched it to the heads, boosted the fuel pressure, headers, and the pistons were not quite zero deck, and cam was . 465"-485" with the 1.6:1 roller rockers, I could spank mustangs like nothing, even a supercharged 5.0, not by a lot, but enough, I had a a center force dual friction clutch and t5 5speed,. Ate one of them, but fairly tough on the t5, I was easy as I could be on it, I eventually went to a 4bbl carb, it would hit 120mph fairly quick for a 3.45 gear, the tpi could not breathe enough to get above 130-135, with the 355, but with the 305, it would do about 145, out on top, not sure what it would do on top end, never got to try, after swapping to the 4bbl, maybe it was the ECM stopping the top speed, because it had the stock tune, for a 305, the only compensation was running a fuel pressure regulator, and cranking up the pressure! I like to think it was near 400hp, I loved those Heads, , I'd like to have another set, and work on them a bit, set at a flow bench for a couple weeks, maybe slightly angle cut them a bit, try for about 60cc chambers,. Maybe larger valves, and unshroud the intake valves, I kinda liked the idea of the TWISTED WEDGE! The center bolt valve covers didn't work that great with the twist, but old style perimeter bolt covers would be fine, maybe more twist? Improve things slightly, a cnc bowl and port would help things the runners seemed to be a bit small! Id like to see about 200cc runners, I think they were 185cc +/-, open them to about 200-215cc if possible and 2.08" valves, back cut swirl polished, the exhaust would probably be fine with bowl and port work, raise the roof a bit, on intake and exhaust, heck, I'd like to work the heads , get crazy with it, weld and grind, then make a mold or CNC scan of them and cast a new head, small chamber large valve, unshrouded,. Angle cut or just chang the valve angle, and push the valves into the head, and unshroud the valves, to flow well to .800"+ exceptionally well for a street head, 58-60cc if possible, and shrink the valve stems, to 6mm or what ever the modern engines use, multiple angle seats, get the mold complete then get a foundry to cast a few , maybe they would sell, raise the exhaust ports and cover rail, raise the intake port slightly, design it so a stock I take will fit, but is truly designed to port match, and and gring the filler from the top of the port flange area, about
.150"-.200, the intake may require welding of a . 250" thick plate, in top of the ports about 2-3" long, with a bead over the top to give it stock looks, all the original intake material can possibly be removed on some intakes, and a filler made from aluminum to fill the port floor, possibly .200" with bolts from the bottom holding them in, using a good epoxy, around the edges and bottom , glue and screw kind of thing, so there is no chance of them coming loose, use aluminum bolts, cut off flush, then braided to prevent backing out, and sand smooth!, Making it fit the port, for the ideal fit and port match, , basically a . 200" high port the Easier way, with . 500" raised cover rail, longer valve stems, get a bit crazy, in places and ways that make a major difference, making what 30years ago would be extremely exotic, kinda use the LS/LT head features, put them in a SBC head, kind of a LS-1, LT/Rec. Port mix, kinda design the exhaust ports after the Chrysler 340 heads, not the shape!, The high port laid back thing, if the valve covers have to be redesigned, or the cover rails tilted, sitting more flat with the intake, and design rockers if need be, making a possible 1.8:1 roller, to reach the exhaust valve, making the ports taller, should eliminate the need to make them wider due to the pushrod pinch, making the ports about 220cc flow in the 300-370 cfm range, maybe, at 1" but should be a .660" max lift head, and capable of 600-700hp on a natural breathing engine, a 355 should be capable of 7500+maybe 8500, but a street able cam -6800-7500 peak should be possible to make peak power there, sitting at the flow bench for weeks, making the changes the air wants, then cast that head, with the as cast port, it should be 220-240 CFM, removing the filler and adding the floor filler, that is shaped just before the short turn to induce just a bit more swirl , helping the flow to pass by the valve, and start a swirl and possibly tumble in the cylinder, work the bowl to get the port angle and flow high as possible, getting outside the shape of a SBC head, and cast valve covers that can be easily machined into almost any. Style someone would want, a traditional , stock inspired cover, to a modern fabricated cover , without welds, the raised rails, with only slightly longer valves, and deeper sunk valves, the valve cover should look similar to a sb2 cover, only more narrow, but making a sb2 styled head with the more traditional SBC placement and arrangement to fit a SBC wit Port locations of SB Chevy, it would at least look cool, it should make power for street race engine, but can SBC head make money these days, when you can get a LS for a few hundred bucks, that is equal to a more exotic SBC, beyond what was stock, and and more likes 7 late 70's or 80"s nascar engine detuned and setup for mpg, basically. Raise the compression a few points, and add a cam, in the .700" neighborhood, and give it the required components to make it live and work even stock heads with 12.5:1 it should make 1985 nascar power basically using mostly stock parts, polished the rods and crank, lightening them and removing stress points, modern light weight pistons, head studs, maybe o-ring the heads, it is more exotic than most any SBC for the cost of time and few parts, making building a SBC more costly, but designing the head, making the power is the fun part, it would be $$$ per det of heads if made, and maybe none would sell, being nothing stock really fits, the salt flat guys would possibly want a set of heads and intake, maybe a modified bbc intake could fit , or the heads possibly be made to use a modified bbc intake, ,. Or a complete new design,.
😐 I really went on a rambling tangent this time! Sorry again !!
No big deal and I am the same way! Got to experiment and see what works and seems you been there and done that!
Never let your wife tell you what to do she will see you like a chump and lose respect for you, stop being afraid of her it's not good for you , thanks for all the car stuff .
@ 4:08, i guess that piston needs to be about .250" large to allow the valve to clearance inside the ring land, so the rings can be higher, I'm a die hard Chevy /GM guy, it's like a religion,
Yes sir and this one is off a canted valve small block which is small bore at 4.125 and wish it had a much bigger bore size to get what you were referring to. Appreciate the feedback James!
What is your opinion on flat plane crank SBC engines?? Id like to build one, with balance shafts in the oil pan, build a pan /main girdle that that fits between the pan and block, only a couple inches at best that holds the balance shafts, maybe incorporate the oil pump in the thing, it would require a timing cover and oil pan custom made, but should help the balance of the flat plane crank, whole bolting to the pan rail, and main caps it should make it stronger! The use of 2 bolt mains should be nearly strong as a stock 4bolr main, with modern pistons, and a split 4bbl intake with a possible valve between to improve power at certain RPM! With a small passage to keep a signal on the carb, use a large plenum, and 3.25" stroke! To 3.40" & 3.50" maybe a 3.0" with 6.125, 6.2", maybe 6.250" -6.309" rods, or maybe a 5.560 rod for the 3.4-3.5" crank to be setup for a lower rpm, (6500 or less) and 6.2" for the 3" for 9k RPM,
Been there and done that! The camshaft will definitely be custom made and that is just a start! Hedder and intake tuning is another issue altogether!
Good info Ben. Love watching your tech videos. Im looking forward to see how my 9.2 deck windsor turns out
It definitely will run!!!
Before piston manufactures raised the rings we would machine two spacers and tac weld them in .then cut the top ring pack .100 down on top of the spaced ring pack it worked great . John Hoffman machine in NJ . He was a genius .
Yes sir the higher the top ring is positioned the more power you found out it will make! Thanks for supporting my channel.
DANG BEN, I GUESS YOUV'E GOTTEN SO POPULAR ALREADY, YOUV'E GOT AS MANY COMMERCIALS AS YOU DO AIR TIME!! AND I'M ALL IN WITH SAYING, I BET NONE OFEM RACE LOL 😃 IV'E NEVER HAD A FILM CREW KEEP POPPING IN THE GARAGE WHILE SHOP TALK AND BUILDING WAS GOING ON HMHMHMHMHMHM! BY THE LOOKS OF THINGS, YOU WON'T HAVE ANY TROUBLE KEEPING IT GOING 😃 MAYBE WE ARE JUST GLUED TO YOUR VIDIO'S! PROLLY SHOULD'NT HAVE SAID THAT LOL LOL!! REALLY ENJOY YOUR CONTENT THOUGH, YOUV'E GOT THE OLD RUSTY COMPUTOR IN MY HEAD LIT BACK UP 😃😉 SO .ILL.
Thanks Carl for your support and please spread the channel to others!
Thank you mr. Alameda, 👍
Thanks for supporting my channel!
I love that the more you share the more "it's all combination" holds true.
So .150 is a safe distance for all or just na?
Thanks again for fantastic videos. You better keep the boss happy. Hahaha
Just NA and you must have that number to get the most out of your engine combination.
Question... Where can people find reasonably priced N/A pistons for SBF's with the top ring around .150"?
Most companies don't even mention this dimension in their spec data on their websites for their pistons.
And the images posted all seem to show the top ring down around .250" or more.
Thanks for all your vids!
I have seen offerings from Mahle showing a good high ring position but you might have to call them and ask for specifics. Ross I feel also has some in their catalogs so this and other will probably show some kind of specs.
@@benalamedaracing2765 Thanks for the reply. Seems Ross primarily makes 2618 as opposed to 4032 forged. Have you noticed much cold slap difference or reasonable longevity between the two alloys for performance street usage?
Chrysler raised the ring pack on the new Hemi.
Thanks as well for supporting my channel thru your viewership!
If they did some engineers in there perhaps getting the hint that it does work big time!
Another great video. Will you be covering the differences of the wrist pins intercepting the oil rings? Thanks
Thanks for supporting my channel! I will touch on these subject on the planning stages.
Love this channel!
Thanks for supporting my channel!
Keep up the great content Ben. We look forward to your next video 😊
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As usual, good info, Ben.
Thanks for supporting my channel!
I have been thinking about hone of bores, I was thinking of experimenting, use a vary coarse stone, with a 20° +/- hatch, then go over then go more fine and 30°-45° and finish with a fine stone, and go 60°-70° hatch. Leaving a very smooth bore with a corse, hatch still hidden to hold oil, for low friction, using thin oil, to be held in the shallow coarse hatch, the texture should appear smooth to a large flat surface, like a piston skirt, but rough to the oil soaking in like a sponge, the thin oil can possibly tighten the bearing clearance slightly, maybe add oil pump volume, sorry again,. But any opinions?
I would follow the instructions of the ring manufacturer just to be sure...
What would say about minimum piston crown thickness for an N/A small block mopar on gasoline and 11:1 compression. 500 hp perhaps.
Thx Ben
From my experience it seems .150 from the top of the piston to the top ring is the ideal distance. Granted that you are running a quench style cylinder chamber instead of the recessed open chamber factory castings. It tends to detonate easier with those types of heads and I would increase the minimum to at least .200 or a little bit more which I really do not like at all. At that level I did .125 from the top but with coated chambers and piston tops.
Specifically like this one sir
Any thoughts on Larry Widmer's roller wave technology on his pistons? Thanks
The man is a genius and from swirl/tumble creating "soft" combustion chambers from years ago really works! He got hammered by the Nascar builders from the mid 80's which was unfair and it is because he was way ahead of most at the time. Even Smokey said the man is good. The wave technology specifies the piston is very much a part of the combustion chamber and I touch on this in one of the videos wherein I said the chambers will be ineffective, if the wrong piston configuration used and w
ill render the combustion chambers mute and useless.
@@benalamedaracing2765 I remember that video of yours! Really appreciate your response on my query, looking forward to more of your videos. 🍻
Ben you’re a very knowledgeable person when it comes to small block Ford I’d like to ask you some questions anyway to get a hold of you talk to you in person thank you
My contact number is on my latest videos.
Great content , and we are talking about how much in gains%?? Between .300 vs .150
I will not attempt an NA engine with .300 ring pack and I will not have a chance against others with high ring location. Losses depends on the engine/cylinder combination.
What can you get out of an LT1 na with aluminum heads. I'm thinking pump gas street
First you should know how much airflow the head is capable of and at what lift it maxes out! From then on it is a piece of cake and we can figure it out.
Ben , what kind of power difference are you talking about from ring pack height ?
Hard to tell because some engines are more sensitive than others but I cannot make the power I am making either street car or race car NA if the ring pack is too low! I need to do a dyno test comparing .150 vs. .250-.300 ring position and that should tell me.