What HP level is the stock crank good for on boost?
06-28-2004, 01:38 PM
#1
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What HP level is the stock crank good for on boost? On say a 370ci what hp level is the stock crank good for under boost reliably? 6?700? And does anybody make a forged stock size crank or would it be better to just go to the 4" for the 408ci?
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06-28-2004, 03:15 PM
#8
The Bull
I've put down some serious power against a stock crank with my car and it's held up fine. With nitrous hitting the crank a little harder then what you are going to be doing with your FI setup, I can't anticipate that you are going to have any problems.
06-28-2004, 03:40 PM
#10
ya 775 dynojet here so far, i imagine the 840rwtq would be the problem
harlan put over 830rwhp mustang on a stock crank..thats nearly 900 dynojet but again tq kills.
this is the reason i have not turned mine up above 16psi.. cuz i dont know when the stock crank is gonna go.
jz97, what is your hp estimate for the stock crank failure, and what is your hp estimate for heads lifting? because i respectfully disagree
when i get the new motor lined up i may just have to take a vote on if i should break the stock crank first or not... it has allready proven to be better than expected.
harlan put over 830rwhp mustang on a stock crank..thats nearly 900 dynojet but again tq kills.
this is the reason i have not turned mine up above 16psi.. cuz i dont know when the stock crank is gonna go.
jz97, what is your hp estimate for the stock crank failure, and what is your hp estimate for heads lifting? because i respectfully disagree
when i get the new motor lined up i may just have to take a vote on if i should break the stock crank first or not... it has allready proven to be better than expected.
06-28-2004, 03:49 PM
#11
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David, I think the stock crank is good for about 900rwhp, of course will depend on rpms. RPMS is what kills these crank, same for rods. The heads lifting, I think somewhere in the 800-850rwhp range, of course it will depend on the setup. If your running a log manifold, it will happen sooner, or at least the likelyhood of it happening.
06-28-2004, 04:14 PM
#16
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crank failures are glorious. you can drain all teh oil and coolant from teh whole block in a matter of seconds
it is seriously a mess when a crank lets go. i have never seen it on an LS1, but i have seen gen1 small blocks fail. my friend actually had such a bad crack failure that 3 of us hung from a long handled crow bar and couldn't get teh crank to budge from teh skirt of teh block. it is wild and a total loss for teh motor sinc eyou are likely to have whacked the heads really really bad when that happens.
later
tim
it is seriously a mess when a crank lets go. i have never seen it on an LS1, but i have seen gen1 small blocks fail. my friend actually had such a bad crack failure that 3 of us hung from a long handled crow bar and couldn't get teh crank to budge from teh skirt of teh block. it is wild and a total loss for teh motor sinc eyou are likely to have whacked the heads really really bad when that happens.
later
tim
06-28-2004, 06:01 PM
#18
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I think 800rwhp is doable with stock crank and I'm going to do it by the fall. Thru my unlocked T400 that would be like 900rwhp thru an M6. So far I have only been spinning my motor to 7000.
06-28-2004, 08:37 PM
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so I take it when the heads lift you have to replace the head gaskets, does it actually damage the heads? I plan to delve into the 15-20lb boost range in the near future. Thanks.
-Sly
-Sly