I would use whichever one has the biggest bore.
What would you build if limited to 372ci - with boost as an option
- Thread starter 71GSSDemon
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That would be the 400 bb then. So, back to about a 3.100 stroke being needed?
Sounds about right. Get on it. lol
I can't do the BBC if meaning Chevy. Both because I just can't put that in my Charger, but also, a chevy motor in a dodge wouldn't pass for record runs.
To bring all this help up to speed. I plan to run the 383 NA for the rookie run and possibly for the 150mph club (if I can get there). Also, have a hand shake partial sponsorship on boost, which should get me to where I want to go, but I should consider a smaller displacement.
Are you allowed to run modern engines?
I could run a late hemi I believe, but would need to have a carb or MFI.
Then there you go. Run a 6.1 and blow the heck out of it.
360 vs 361 or destroked 383/400. B you got bore size, 5 bolt heads, probably more head options, steel crank even though 360's crank is proven tough but this ain't a 10-15 second drag race, they seem to handle more power. 360 cheaper pistons probably, pin height ?
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Kinda my thoughts. The big block has more head bolts for more boost, or how big of a deal is that honestly. I wouldn't think more than 18psi or so. This would be 5 miles of trying to get up to speed. Sustained high speed, high boost, high rpm for the measured mile from 4-5. Would be ideal. Honestly @TT5.9mag latest build would be perfect for power and displacement.
Can a stock crank be turned down to 3.1" ? If not a 383 would need like a 3.22", bigger bore is better but your probably not building a 800-1000+ NA + boost motor, a 4" bore goes pretty far power wise so even a 4.185" probably be good enough but yes 4.28" - 4.40" is even better just wouldn't expect crazy power gains unless using heads that need it.
TT5.9mag
Two atmospheres are better than one
I would only choose the big block for the physical strength of the block itself. The very first thing you need to do is work out some math and decide how much power you need to get where you want. Then decide what path gets you there. A small block making 2.9hp/ci is a hell of a thing (~1100hp@372ci) and it’s possible but for longevity an aftermarket block may be the best decision at that point if staying small block. A big block might be better for a stock block choice in that case. And a gen 3 hemi might be the best of both worlds. Don’t forget you can pull plug wires and make runs at a lower displacement so building 372 for a 372 class may be the wrong choice. A 454 with one wire pulled is 397. So you could possibly fit the car in multiple classes if you think that way. Engine builders hate that though. First thing first, how much power do you need?
The other issue with the R motors is the prelube and oil heaters before each run. Not that it would be a deal breaker, but watching those running the Nascar motors do that each run seems like a pain without a crew helping.
Thank you Sir. An honest 700hp should get me to my personal goal. Then likely need to have 1,000-1,100hp for chasing an actual record in <372ci class. Can't have too much. Jerry has the 8553 Daytona which has aero advantage over me with C500 trim, but with 950hp at the crank, he has gone 239mph. There is a Cyclone Spoiler that runs there also (closer to my aero) and 600hp got him to 193mph. In the <372ci class, record is 224mph with boost. in the 373-439.99ci it increases to 246mph.
TT5.9mag
Two atmospheres are better than one
An oil accumulator makes that pretty easy. We run one on our truck and before every fire up we pump oil through the engine with it. And you don’t need an oil heater, just run the engine for a bit. We run our junk on jackstands to heat the engine oil, trans fluid, and diff before a race and it only takes 10 minutes or so to get some heat on the oils.
I think people have ground the other way to 3.55" so that be 3.21" might be possible.
Ok, thanks. I don't know much about the Nascar motors. wasn't sure if they need something special, seems everything I have watched, they all do the same thing, spin the dry sump and run through an oil heater.
So, this is all great chat and ideas. I don't know the best way to accomplish what I want, but I like to try to formulate a plan if that is possible. Then parts can be slowly gathered.
Thank you all for chiming in. Feel free to continue - even if telling me my broke *** will never see what I want. That would be great motivation to prove it can be done.
Thank you all for chiming in. Feel free to continue - even if telling me my broke *** will never see what I want. That would be great motivation to prove it can be done.
TT5.9mag
Two atmospheres are better than one
“Ok, thanks. I don't know much about the Nascar motors. wasn't sure if they need something special, seems everything I have watched, they all do the same thing, spin the dry sump and run through an oil heater.“
They do that because that’s their best option. You can accomplish the same thing a different way. The goal is to build some heat in the fluids before running it and there are many ways to get it done.
They do that because that’s their best option. You can accomplish the same thing a different way. The goal is to build some heat in the fluids before running it and there are many ways to get it done.
Maybe 18-20psi in my 383, CSU blow thru carb, timing retard with boost, C16 fuel and a big diaper to catch the parts. Oh, and crew members all need to bring a shovel for parts. Then Tim can announce a "yard sale" after my pass....
TT5.9mag
Two atmospheres are better than one
I could make a blow through 383 live on 18psi with c16 no problem. And I think it would make the power you need. I wouldn’t rely on any electronics to yank timing. Run a locked out distributor and it will be fail safe. You don’t need a curve in a bonneville engine. In fact you need to dump off some torque so it’s beneficial not to have optimal timing at peak torque rpm.
Interesting. We can talk more about this. The only reason for this thread was to get that same engine under 372ci to lower the record from 246 to 224.
As a participant, do I supply the shovels for you all? Like the flat wide snow shovel type I think...I’ll be there to announce “yard sale” as well. That’s one of the reasons I’ll be going.
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