Is this a cast or forged crank? If I remember correctly forged has a one inch wide casting line. This one is very thin.


http://webpages.charter.net/seanthomas/crank1-1.jpg

thin line cast, wide line steel.

Bob

Crap, that's what I thought. Aaaaah, well. :(

Whats wrong with cast? :confused:
You know how may cracked steel cranks I've seen? :eek: (quite a few)
I've never seen a cracked cast crank.
Just my experience.Sean,don't take this the wrong way..from my viewpoint,it looks like you're setting yourself up to spend alot of un-necessary money.

Unfortunately I'm going to have to test your theory, Chris. :D

I don't have the ka-ching to buy a forged crank, anyways. I am, however, going to lay down the coin for some new slugs, since I've got to replace them anyway. The valve reliefs on the pistons that came with this motor aren't going to handle the lift of the cam I'm stuffing in. I'll probably be picking up some SRP's. That'll help lighten the reciprocating assembly a little.

Thanks for the help!

I am the unlucky owner of a couple of broken cast cranks and havent broke any forged ( yet). But I do agree highly with Mr 4 speed about cast cranks. The things I have put cast cranks thru its amazing I havent broke more according to others. I had one in a 13-1 355 and spun it to 8200 + for more than 6 years of racing. Its still sitting here collecting dust after it needed to be ground again ( .030/.030 under now ) Go for it ..........

Sean

Don't worry too much about cast cranks. They can take quite a bit of abuse. Some stockers use them because for the lower horsepower engines they are lighter than the forged and they can rev faster due to this.

The reason not many cast cranks have cranks is because of the nature of the manufacturing process when it gets a crack it wont take long before it will actually break. Forged can take more abuse and longer than a cast unit because of the grain structure of the material created by the manufacturing process.

But unless your making 550+ hp or alot of rpm i wouldnt worry about it. I haven't seen it but have heard of people running in the 7000 to 8000 rpm range with a bbc crank in a superstocker. But it was gone over with a very very fine tooth comb to make sure there were nothing wrong before it was put to that abuse. Like I said I was told about the rpm levels I never saw it so take it for what it's worth.

Todd

when I did my motor, i did a little research, and what i figured out was that a cast crank can handle up to 650 hp. I guess it can, go ck my motor out and I have whats in it also. Pretty much a budget motor. It has not broke "yet".