pr_lt1

Im planning to build my Lt1 engine to .030 over (355) with a Scat or Eagle forged rods, probably I-beam, Mahle powerpack and use my existing crankshaft. All this, naturally aspirated with Ai 200cc heads, ported intake, valvetrain etc but wondering how strong is the stock crankshaft. Any comment about it, super welcome, Happy New Year and thanks a lot in advanced.

AChotrod

iTrader: (17)

Amazingly strong. Ive never seen one break.

RamAir95TA

iTrader: (2)

If it's in good shape and spun within the normal RPM realm of a typical performance SBC, for all intents and purposes I'd say they are just shy of, indestructible.

bowtienut

iTrader: (1)

Well over 500 fwhp here on rebuilt bottom end with ALL stock rotating assembly except for the ARP rod bolts. spinning to 7100 rpm for about 100 passes now.
I know of quite a few that have held up under much more hp (boosted and/or sprayed) for many years without issues.

BOLO

iTrader: (40)

I remember a well known engine builder on this site, telling me that the LT1 stock crank, or stock bottom end can endure controlled high rpms no problem, it's detonation that kills it. As long as good quality gas is used it will last. Knock on wood.

bowtienut

iTrader: (1)

x2

vtec

iTrader: (1)

mine has endured dang near 700 at the flywheel so far.

pr_lt1

Thanks for the input guys, gladly welcome. My car is stock with a few bolt-ons by now with 117,000 something miles on the clock with no abused so i guess im gonna stick with the stock crank period. Just wanted to know the capability of it for when i want to dig into the engine. Thanks.

jlpz

iTrader: (8)

Those suckers can take the abuse, I rather go stock 3.48 GM than a scat or eagle crank with the same stroke.

BizZzatch350

iTrader: (33)

Plenty of 35x and even stock short block LT1s have been 9s on Nitrous with it , I can think of three, one 355 and two stock short block cars, one of them even posted in this thread. I'm jlpz, I trust the stock crank better then I do a cast after market crank.


I knew two local guys running 9.6-9.7s with stock short block LS1s on tons of gas, both light cars but a lot of their life was all in the tune. I remember one of their h/c set barley made a little over 400rwhp when it was in a six speed 10 bolt car on motor. But as evidence of what Vtec has run, stock short blocks not as weak as people like to make it out to be. I always heard nitrous wont kill a motor, lack of fuel will though

hitmanws6

iTrader: (20)

AleksSS was running a SR 350 setup making 500 at the wheels at 8000 rpm and was running high 10s, so its pretty strong

BizZzatch350

iTrader: (33)

Time Herrington was doing the same for years with his 355 as well.

blakez28

iTrader: (6)

I've never heard of a stock crank going bad. I've always heard if you don't need forged internals don't go with the added weight. I'm doing a le2 lt1 combo with the stock crank and I'm hoping she holds up.

wow are you serious about the 8,000 rpm? i though 7100ish was high for these cars

SS MPSTR

iTrader: (1)

For the OP set-up, it is plenty strong. Spend money elsewhere.

pr_lt1

Nice videos Bolo and a really great looking camaro.

BOLO

iTrader: (40)

Thanks. Good luck with your project.

1BadAsZ

this is good to know i may be able to spend more on heads n other stuff then having to buy a 2 grand rotating assembly

1BadAsZ

doesnt a 355 have to rev higher then a stroker in most situations? and what is better to go with forged i beam or h beam rods?

speed_demon24

iTrader: (6)

This. Detonation and oil starvation are what kills most engines even though people like to blame other things.

94fixerTA

iTrader: (5)

I broke one trying to get an old motor apart. Apparently it doesnt hold up to a 12 lbs sledge when your trying to free up a locked block. Lol