I have eagle rods je pistons. Tryin to pick out a crack shaft for my turbo 355 project. The block has 4 bolt mains. Question is how strong is the stock crank? Should i go ahead and put a sledgehammer or a dragon slayer crank in? looking for a bout 600-700hp

 

your going to get a let of opposition on this, some are going to say you can keep the stock crank, some are going to say you need a new better unit...

 

i wouldnt trust the stock crank past 550rwhp. Many people have put it past that but they dont do it for that long. And if you going to bother to build the bottom end that far, take it all the way. If not, you ll kick yourself later.

 

I'm running a forged Eagle crank, not very expensive and defintely stronger than the stocker.

 

Has anyone ever seen a stock LT1 crank break? Just curious if anyones heard of this and at what level/circumstance etc.

It seems most will put a forged piece in there for peace of mind more than anything.

-Scott.

 

Get a nice forged crankshaft. With your 4 bolt mains and forged rods/pistons, You will never have to worry about breaking something. I didnt put in a forged crank and I'm regretting it...FWIW im making 500+ rwhp (5600 ft above sea level,623 corrected) with the stocker. Go ahead and put a forged crank in and go out and have some fun.

 

If I was doing a budget built, I'd have no problem using a stock crankshaft. I for one have never heard of one breaking.

 

I should be going into the 9's at the ltx shootout on the stocker and sprayed it on the old setup to around 875 crank HP.

 

i know theres a guy on the fastest lt1's list in the mid 9's on a 300 shot. But if it were me i would rather not have a weak link in my shortblock. Not to say that its weak but its not a forged piece.

 

Does it have to be a forged piece though? Personally, if you're sticking with a small overbore as possible or just going with a standard .030 over rebuild and NOT wanting to go 383 or rev above 7K RPM, my money is on the stock crankshaft being just fine. I say this: Find a stock LT1 crankshaft that's broken, and not a secondary break from immediately catastrophic engine failure somewhere else. You probably won't.

 

I understand where your coming from.

 

Many bottom ends are overkill and a trick forged crank does NOT make power. If this is NA, it won't make 6-700hp anyway and a stock crank will be fine. A supercharger is especially hard on the crank due to the increased power and the load on the nose from the belt. For a SC car, definitely get a forged crabnk (Callies Compstar best in the moderate price range).

Rich

 

Really good point there. That one escaped my mind.

 

Don't mean to steal his thread but i'm also wondering this. I have a GM Forged crank that I was going to use in my setup, looking for about 650rwhp. Would it be better to use the forged crank or keep my stock cast crank?

Btw its a forged crank out of 86+ trucks I believe. Part #: 14088532