pullmytrigger

How do the GM cranks stack up against the ton of different aftermarket cranks out there in strength, quality and price????

pullmytrigger

nobody??

cstraub

Tolerance wise the GM stuff is top notch compared to the budget 4340 stuff coming from over seas. When you get into the higher dollar forged stuff and the billet then they are spot on.

The GM stuff is hardend but not nitrided and the 1053 material is somewhat brittle but these cranks will take some power. How much? Depends on tolerances setup in the engine and application.

Aftermarket stuff when getting into the larger stroke stuff offers profiled counterweights that reduce windage which reduces oiling problems. Radius filets on the pins help to strengthen the crank when under load.

If your asking if an OEM crank will stand up to say 600HP. Yes. Are there benefits to an aftermarket? Yes.

Strip Poker 388

iTrader: (6)

I built a blower motor for my old Scarab a while back and had Jim Oddy dyno it and they helped with some advice on the build up also. He said a GM crank was good to 800hp. after that they recommended a aftermarket.I ran a stock GM crank with a lot of radiusing and deburing for 3 summers at 762hp.Its looked good when I tore it down . I went to step it up then I went to aftermarket everything .But the Crower billet stuff

As far as say like the Eagle stuff , its cheap,you have to check all the clearances , do not take it fro granted!!.I would say its a step up from a stock GM crank or Rods.There's a lot of guys out there drag racing the Eagle stuff with lots of NOS. and Ive seen it hold up , But like anything they do come apart when abused

Like Chris said depends on what your trying to do, if you don't mind spending the money Its good insurance with the import aftermarket or step up the real 4340 stuff$$$$.

I just ordered a Crower billet crank for a friend for a Turbo Buick GN it was $2800.00 laid in and it included a $250 sure charge because of the metal shortage .There saying 9 weeks on getting a set of rods now


GoodLuck
Rob

mopower

I've had good luck with Eagle stuff but like strip poker said "check ALL the clearances". Their QC leaves a bit to be desired
The worst I ever saw was an out of round rear main seal surface. It was checked and it miced ok. When running it would dump a Qt every 10 miles or so
The only way it was found was in a lathe(on extremely slow speed) with a dial guage on the seal surface.

BTW , Eagle did make good on it
But didn't cover the aggrivation

Strip Poker 388

iTrader: (6)

Yea My last set of Eagle rods were on the small side I had to resize them and I have seen the cranks off also. I had a buddy had one crank that was way out , they replace it but he had to pay shipping to there. But like any and all manufactures a good engine builder ck's the clearances . I hope I have seen most reputable engine builders will not use the Eagle/import stuff because of having to warranty it or there reputation on .

I have buddy engine builder had a guy [bro drug dealer$$]at the drag strip chunk a BBC Crower billet crank out the bottom end in the water box.He blamed the engine builder . The recall on the tack said 8800. His Buddy's said he purged the NOS before the burnout , so he was on the nos doing the burn out.So ya never know

Rob