I have a crank my friend gave me that needs turned.

It is a scat 9000 crank and I am only building up say 400-425 hp 383. Nothing too radical.

I have not been to my machine shop yet to have it checked. What is the safe range to have it turned. I know that 10 under would be fine, but what about 20 under? It has one bad scratch that 10 under might not take out.

Would you guys use a crank that was turned 20 under?

Remember, its a freebie so I really cant lose if I dont use it.

thanks.

 

U'll be good up to 0.030".

 

it's good for anything you can buy bearings for. there's a reason someone gave you a scat crank. considering how cheap cranks are i'd keep looking, especially when you add it the cost to have it ground undersized. call autozone. you can buy a gm crank from them with bearings for less than 200 dollars. consider bearings are going ot cost you around 75 it isn't bad price.

 

Is the GM crank going to hold up to say 450 hp?

I had also looked at the eagle and pbm cranks. I dont need forged. What would you suggest then.

 

i'd worry more about the finish and straightness of a crank for a 450 hp application then i would if it's strong enough. in other words have the crank inspected and blueprinted and don't get all wrapped up in running a high dollar piece and thinking that's the end of it, just laying your money down and having a good part to run. if you believe DD2000 i built a 350 few years ago for my sons car that was over 450hp and ran a stock cast crank. for the record i don't really believe it was over 450 hp like DD2000 said. my guess would be more in the 415-425 range.

 

I had thought about a 355 with my stock crank. Probably would make all the hp I am wanting.

As far a getting everything straight and balanced for the 383, I have a great machine shop.

I just dont want to put a crank in a motor and have it fly apart after everything is said and done. Id rather be safe than sorry.

 

you'll break a lot of other parts long before the crank breaks, usually the cranks breaks because something else broke first

 

Do you think the stock L98 crank would be safe up to 425 hp in a 355? Say spinning it to 5800-6000 rpm?

Of course I would have the cranked checked and polished.

 

You're going to have a tough time getting a 350 to put out 425 HP at 6000 RPM or less.

But yes, at RPMs below 6000 with no nitrous, a stock crank is fine, with the appropriate minimum maintenance machine work done to it as you describe.

 

I figured with the right head, cam, and intake combo it would be close. Maybe 400 hp and might have to rev to 6500. That is the max rpm range I would want to go.

 

Off the subject but couldn't you just get a 350 put fast burn heads and an LT4 HOt cam and get 430 HP?(aka ZZ430)not too tough. I don't think that people take the HOT cam to more than 6000 rpm I don't. My engine dynoed at 408 hp with vortecs and HOt cam at 5600 rpm, that's close.