Crank Calls

[TurboGTU]

I was wondering if I have a forged crank or strong crank. It's off a 94(non-3100) 3.1l grand prix. It has a thick parting line. The one the 2.8 I had in the beretta it had a thin parting line. On SBChevys the parting line is soppose to tell if forged or cast. Is my (3.1) crank hardened,forged,cast?

 

On a 2.8 I rebuild for a S10, The crank went bad(mains went out). It had a thick parting line and when off the ground, I hit it with a hammer and made a dull sound, when I got another crank off a 3.0 Vulcan from a taurus w/a thin parting line, the crank made a ping sound.

 

So does that mean the 2.8 thin parting line crank is forged?

Do I have a weak crank(3.1 off 94)?

 

Any info is appreciated.

[eclipse5302]

I highly doubt the crank is forged. The parting line just shows how clean of a casting it is. The TGP crank is supposed to be the strongest 60 degree v6 crank. And it's not forged.

 

It is basically a 3.1 crank, with the casting flashings removed and with rolled fillets. Those are the radiused edges of the journals. Instead of being cut into a radius, they are rolled. This, along with the cleaned casting flashings reduces stress risers. The casting also looks like a special one, because of the cleanliness of it...compared to a standard 3.1 crank.

 

Jason

[TurboGTU]

So I just have a quickly cast one. Nice..!... Will the crank go before the 400/400 mark I plan?

[eclipse5302]

Uhhh, hard to say. If you're really planning on trying to hit that mark you should get a TGP crank, because it's going to be the best crank you can get for your engine (short of paying a ton for a custom forged piece). And since you'll be spending all that cash to get 400/400, a few extra bucks in the for of a TGP crank should be doable.

 

Last I heard, Curtis Walker ran 12 something in his Turbo Z24 and he uses a stock TGP crank (I think)...and that engine is making some serious HP/TQ. Check his site out, hes got tons of engine pics there from his rebuilds.

 

http://www.turboz24.com

 

Jason