I would like to know what are or could be a safe limit to a stock bottom end... I'm looking into a turbo setup..
I'm heard everything from 500rwhp-600rwhp and then some..
I'm planning on changing the head to lower compression around 9.5-9.9..
You should be fine up to 12 PSI and 650 RWHP with complete stock engine. Im boosting 10 Psi 627 RWHP 500RWTQ Methanol injection..and have no problems. Also running at that high HP you have to have meth.
Goodluck!
I ran 10psi with meth above 5psi on stock LS6 with no adverse side effects whatsever. I have upgraded my motor soley for my quest for sic fun, but I still have the perfectly running LS6 long block. Haven't decided whether to sell it or keep it for matching numbers. Depends on how long I plan to keep the c5 I guess.
I believe the plan is to run around 8psi and not meth with the Twin Turbos.... I'm told this should yield 550-600rwhp...
Just advice, and just from what I've been told, but hope it helps.
Different pistons is the correct way to lower compression, thicker head gaskets is a nono, modified heads is a compromise/patch but much easier than pistons to get at.
Meth above 5psi cools the mix, keeps the temp down, and helps prevent detonation. meth kit is 5 cnotes, but may prevent fatal engine failure. I haven't seen one implode or melt myself but I got insurance and ran meth.
As for what I've seen with my own eyes,
At 8psi my stock ls6 twin hit 551 on the dyno, 598 at 10psi. I still have these dyno sheets.
Different pistons is the correct way to lower compression, thicker head gaskets is a nono, modified heads is a compromise/patch but much easier than pistons to get at.
I think that is an overstatement.
Both heads with larger combustion chambers and dished pistons are appropriate methods of lowering your C/R....either seperate or in combination.
I think that is an overstatement.
Both heads with larger combustion chambers and dished pistons are appropriate methods of lowering your C/R....either seperate or in combination.
Mike
Thanks for catching that Mike, I concur. It was thicker gaskets that I had heard would cause problems and was told to avoid that technique. While I do have custom heads, I believe most, if not all, of the lowering on mine was done with the pistons since it made sense to forge everything down there anyway.
On stock internals, enough boost to yield 500-550 rwhp. After that you can throw longevity out the window. I've read that plenty of guys are doing OK with more rwhp on stock internals, but I've also read that plenty have lost it as well. If you stay around 500, there won't be an issue. I ran at 575rwhp for quite a while with no issues, but then maybe I was just lucky!
is it a differance if your running say, 550rwhp on a supercharger or 550rwhp on a turbo???
I would assume 550 on a super is tougher on an engine than 550 with a turbo..
550/ .85 =647 at crank + 60-80hp to run the super is about 707 to 727 at the crank vs the turbo is still making around 647 crank hp....
I'm not sure just asking the question.... it seems the super is/might be harder on the engine....
On stock internals, enough boost to yield 500-550 rwhp. After that you can throw longevity out the window. I've read that plenty of guys are doing OK with more rwhp on stock internals, but I've also read that plenty have lost it as well. If you stay around 500, there won't be an issue. I ran at 575rwhp for quite a while with no issues, but then maybe I was just lucky!
Yea, I bet some motors are just right, others may have a flaw only revealed under stress.
Zrod- How long did you run the car without an issue???
I forged the motor, but not now with the turbo install. If i can get 1 or 2 season (5k-10K miles) out of her before the forging, i'll be real happy...
Zrod- How long did you run the car without an issue???
I forged the motor, but not now with the turbo install. If i can get 1 or 2 season (5k-10K miles) out of her before the forging, i'll be real happy...
I think I ran with that power for about a year ( 7,000 miles).
Got nervous and went forged 402 ala A&A.
Zrod- if 550rwhp can give some measure of longevity, what do you think 575-600rwhp might give you- if tune and fuel are not an issues???? 10K, 20K miles worth of reliable miles??
I plan have the car tuned at Spedd inc, which is know for Conservative tunes on N/A let alone FI... Would adding a Torco add much of a safe net?? I'm to far from 100octane fuel.
Any thoughts on experiance with the LS7 clutch?
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