What is the opinion of using a forged GM crank vesus an aftermarket such as a Scat? The application will be a blower motor 600 - 650 HP.

Has anyone had problems with the GM forged cranks?

What is the advantage of 4340 or 5140 steel over 1053 steel?

Thanks,

Kirk

Basically the differance is in the quality / hardness of the metal. I am sure you will get more or better info on the differances.

As for a stock GM forged crank I would not be afraid to use one if the price was right. Make sure it is straight. Just my opinion.

Scat has problems with consistency. You never know which underfed shoeless refugee was running the CNC crank grinder that day.

Buy quality American aftermarket or stick with GM. The GM crank is good to 6400 rpm and 750hp or so.

I, personally, would NEVER use a Scat crank in my own engine. Just my preference in not buying Chinese steel. That goes for Eagle as well. I have also seen several of these cranks in more than one piece.

Go with the GM. If you decide to go aftermarket, use any of the following:
Lunati
Callies
LA Enterprises
Cola

DAVE

I agree, you wont have any problems with a GM crank

I'm running a GM crank in the blown 468" I just built, and it's making over 700HP.

This is exactly why I don't have a problem paying for this site!!

Great info, thank you everyone. I will stick with the GM. I was just concerned with the 1053 steel.

Eagle cranks suck!! I can attest to that unfortunately!

You can probably look into the GM farther. They might have a different manufacture making the GM performance parts cranks. That could give you a idea of quality of the crank..

Like for example the crank used in the GM 383 is made by cola.. a nice $900+ price tag on it from Gm..


another example...most of the HP parts from GM are usually from some other manufacture.. most of the valvetrains and cams are either crane,comp or luniti parts

just a idea and my .02

I favor the GM cranks over the Scat.

GM cranks in this application are just fine, just be sure the piece is straight, crack free, and the bearing surfaces are right. The quality and strength of the GM forging are plenty good here.
Also, BUY AMERICAN!! The US made pieces are much better and the cost of imports can ultimately be more than the initial savings!