EVIL87

iTrader: (1)

anybody now the max horsepower I can safely make on a gmpp 4.125 crank?

engine started off as a gmpp crate 454lsx
I upgraded a couple parts

here is the specs
gmpp 4.125 forged steel crank
compstar 6.125 rods with arp2000 bolts
cp custom 4.210 bore 11.5 to 1 compression pistons
ARP main studs
ls7 6 bolt heads aftermarket cnc ported and polished
ARP pro series head studs
stock ls7 rockers 1.8
cometic head gaskets
holley hi ram ls7
holley tb
160# injectors
obx turbo headers
s475 1.32 ar t6 turbo (will be upgraded later)

I know the turbo is small for this build but I only want 1000rwhp
and I will be running q16 or e85 and meth injection.

this is going in my 69 Camaro with a th400 and 9" outback

any input would be appreciated.

Blackpanther99

iTrader: (8)

Really dont have much knowledge on those cranks but I think it will meet your goals or at least you will be close to the rating. I would say 950-100+HP... Then again idk much about those cranks or how durable are they. Hopefully someone more knowledgeable will come in and help you.

KCS

iTrader: (20)

Standard deck height block?

EVIL87

iTrader: (1)

Yes it is standard deck. Also considering a new comp turbo triple ball bearing 100mm compressor t6 housing, if the crank can hold it

DietCoke

iTrader: (18)

Rods will go first. The stock crank is good to 1000, much less a forged one. Make sure thrust is within spec and the converter isnt going to push the crank into a bind, and you're golden.

KCS

iTrader: (20)

Pistons will go first. A 4.125" crank in a standard deck block leaves you with a piston compression height of about 1.05". That's pretty thin for a combination pushing 1000whp and may not last very long.