79MakoL82

The Salee Cheverolet site says the crank on the ZZ4 is forged steel and I've seen on other sites that it is forged steel. I've ALSO seen on other sites that say that it is nodular iron. Whichun is it?:confused: Just collecting info for my future build up when I win FREAK'N LOTTO. :smash:

BSeery

This is information from the "H.O. 350 Installation and Service Information" guide made by GM (PN 12485074 Rev . 7/98)

In that guide they say that in the ZZZ to ZZ3 motors they all used a 1053 Forged steel crank.
For the ZZ4 it says "LT4 Nodular Iron with rolled fillets"

Hope that helps.

79MakoL82

H-m-m-m-m-m-m-m-m-m-m :confused:

Is Salee Chevrolet mis-representing?

BSeery

Pace (www.paceparts.com) also says that it has a 1053 forged crank.

Maybe my publication is wrong, but it was written by GM.

If you call Sallee -- talk to Tom in parts. He is a good guy and can give you the straight answer.

theandies

Also check in the Jim Pace GM Performance Parts catalog. It list all the internal parts part numbers used in the ZZ4. You can then cross reference it with the individual cranks sold in the catalog. If you don't have the catalog, I'll post the part number and description when I get home from work. If my boss is reading thisI'm ON MY LUNCH BREAK:lol:
John


[Modified by theandies, 12:12 PM 11/15/2001]


[Modified by theandies, 12:13 PM 11/15/2001]

81vette

From what I've read, the first engines used forged cranks....then GM decided to put in a cast crank for 2000', then they went back to the forged crank for the 2001' model. Better hurry up and buy one......as next year it'll be a cast crank again!!! :D :D :D





[Modified by 81vette, 12:24 PM 11/15/2001]

Hershey

79Mako, my latest GM Performance Parts catalog lists the ZZ4 crank as #12551485- Nodular cast iron with undercut and rolled fillets. Hershey :chevy

theandies

This one is getting weird. Jim Pace catalog for 200 list the PN #12551485 "nodular cast iron with undercut and rolled fillets". Then I went to the crankshaft section of the catalog and it lists PN #12556307 for the ZZ4, LT1 and LT4 "This Crankshaft is used in the new ZZ4 engine as well as the past model LT1 and LT4 Corvettes. The crankshaft is nodular iron with undercut and rolled fillets for addes strength and reliability. One piece rear seal type". On the same page as that Pace lists PN #12556307 "This forged steel crankshaft is used on all 2nd design ZZ4 350 engines after November 1998 and can be used to replace all cast or steel forged crankshafts on ZZ4 engines only".

Same part number and same price. Weird. I'd call Sallee or Jim Pace and get the real scoop.
John

79MakoL82

Just spoke with Jim Pace parts. They claim according to the GM Performance Parts catalog, it is "definately steel". They may have used iron in the past, but it is currently steel. Still :confused:

79MakoL82

According to GMGoodwrench.com, it uses part #12556307 CRANKSHAFT . Can anybody identify this part number?

79MakoL82

OK, from the GM performance parts site:

12556307 - Crankshaft (Forged Steel)

I guess it IS forged steel. :D