[02gt2v]

Hey guys, I got a spare engine and want to slowly piece together parts to build the bottom end to hold about 600rwhp....I kno forged rods and pistons are a must but how strong is the stock crank...who has actually broken one....Im not looking for fake numbers that people say to try an sell stuff....

[roosgt!]

I think its somwhere in the range of 600hp.
If it was me and I'm building the motor I would put a new crank in it, why spend all that money on that type of a setup and not upgrade the crank too.

[DickH]

cast crank can take 600hp, as long as you keep the RPMs reasonable. You will probably be told to get a cobra crank, they aren't expensive and will take whatever power you could ever make.

[BakerFX4]

man, there is has been some go over 600. I was at 599rwhp with my stock crank but spun a bearing.

Ive got a set of rods and pistons. 4340 MMR H beam rods with .20 over Manyley 18cc pistons. About 2000 miles on them or so. If that.

[02gt2v]

What are u asking for them...and did the rod get damaged from the spun bearing

[02gt2v]

I will honestly like to sit at 450-475rwhp ( superflow dyno) on the supercharger and occasionally spray a 75-100 shot on a separate fuel supply just for the heck of it....plus the torque would be ridiculous

[86er]

Never Enuf on here I believe has spun a stock crank to 8k and made some decent power to boot

[BakerFX4]

I havent pulled them out yet. I will have the rod checked before i was to sell them. I just pulled the pan and saw my problem.

[Nitmare67]

No need for a forged crank in most applications. The factory cast crank is much lighter also. My crank after all the work was done to it was something like 14lbs lighter than my friends cobra crank. For a build under 600rwhp I would run the stock crank. Spend the money else where.

My new engine build is 14lbs boost, h beam rods, 16cc dish forged pistons, New stock PI heads, CMS stage 2 blower cams. I'm shooting for over 500rwhp. This is a budget build honestly.

[02gt2v]

Thanks guys....I also feel like the stock crank is fine ..especially if prepped right I think it'll be fine at less than 600hp and 7k rpm

[limited]

you may not need one, but if you keep looking for a cobra crank you can usually find a good deal on one. the peace of mind is worth the couple hundred to me

[bulloch27]

Check NMRA Real Street. Almost everyone is running in the 9s and almost everyone is running stock cast 6 bolt cranks. That says enough in my book.

[mustanginky]

im at 414 rwhp and 450 rwtq with my 2v crank spun up to 6300 rpm. i think rpm kills stock cranks more than horsepower does.

[stal94gt]

im late on this topic but a few things to consider when choosing a crank. for a street driven car making 600 or less hp turning under 7k rpms the cast crank is fine. hell i would push it even higher with no stress about it. but where to consider going to the steel crank is when you have a car that sees alot of track time on slicks. steel cranks rob hp but the gain from them is their ability to flex. on hard launches with trans brakes or leaving the line off a 2 step manual it sends a shock threw the crank and steel cranks are able to handle much more abuse. many may say they have never seen a cast crank fail but 99% of people dont run their car like that with over 600 hp.

[bulloch27]

Originally Posted by mustanginky im at 414 rwhp and 450 rwtq with my 2v crank spun up to 6300 rpm. i think rpm kills stock cranks more than horsepower does.

Real street cars are mostly in the 525 hp range....... they do, however shift in the 8000 rpm range. Decent parts assembled well can make it happen.

[02gt2v]

You make a good point stal...but in my case its looking like the stock crank will do just fine...I rarely get a chance to go to the track...and i don't rag my cars that hard anyways...
and of course ill have the crank turned if needed and proper balance is a must