C2- L78 piston rods

[Robert M.]

There is a set of rods advertised on ebay as original and unused for a 396/425 corvette engine. How would these be positively identified as real?

[Joe L.]

Re: C2- L78 piston rods

Rob------

If they're in the GM boxes, the part number will be GM #3856240.

If they're not in the boxes, it becomes more difficult. However, the following may be identifying features:

1) rib on the rod cap
2) blue paint daub somewhere on the rod

Now, comes the further question: why would you want these rods? While these rods are certainly ok, there's nothing really great about them. They're 4340 steel, shot-peened and magnafluxed, but they are 3/8" rod bolt rods.

A MUCH better plan? Use rod set GM #12496661. This set includes 8 of the GM #10198922 rods. They're 4340, shotpeened, magnaflux inspected, AND theyre designed for 7/16" rod bolts. Far superior to the 3856240 and you can purchase a set of these for a very attractive price. They're not as good as some aftermarket rods, but they're FAR better than anything you'll EVER need for street operation. Until full car, x-ray inspection for NCRS/NCCB judging begins, no one will be the wiser, either.

[Joe R.]

Re: C2- L78 piston rods

Joe,

The X-ray (actually 3D CT)machines to accomplish this are in R & D as we speak. They should be on the judging field by the National Meet in 2050. Hope to see you there!

Regards,

JR

[Robert M.]

Re: C2- L78 piston rods

Joe, As usual your common sense and knowledge shines through. Fortunately I don't need them as my engine is fine. I just wondered if they were a commodity worth having on the shelf. You answered that question.