Hello all, having an issue with a flywheel I purchased not fitting my build.
I've got a 86+ 350, 1 piece rear main seal, casting number 10054727. It's going in a 1965 Jeep J-300 Gladiator, mating to a T90a1 3sp, with an advance adapters adapter kit. Doing this on a mild budget, not going crazy building the engine up or anything, leaving it as I got it.
Purchased a Jegs Flywheel and clutch, Flywheel part number is 555-601256, description states its for 1986-1993, 168 tooth externally balanced. It doesn't even come close to fitting the bolt holes on the crank. The crank has the standard 3.00" bolt pattern, while the flywheel has a bolt pattern of 3.125", and I have been completely unable to find anything anywhere that says that a SBC came with anything close to 3.125 for it's bolt pattern. See pics. No amount of turning the flywheel makes them match up, the center bore fits PERFECT, but not a single bolt will go in. Did Jegs mess up, or did i accidentally smoke something and buy the wrong part, despite the description matching? It says that it replaces GM part number 10105832, which when doing some googling, has a 3.00" bolt pattern.

 

If you’re certain you received the part you ordered (check the flywheel for a stamped number to confirm) I think your best option is to contact jegs and see what they can tell you. They have more than 1 flywheel/clutch kit for SBC so it’s probably a matter of verifying what you ordered is correct for what you have.