Think twice about using that 403

March 1, 2012 | By Richard Prince


This is one great magazine I love to read from cover to cover. It also has given me the desire to start my own project, which is a 1976 Olds Omega. My question is about an engine swap. I want to put an Olds 403 cid small block in the car. The car came with a straight six engine. Could you tell me what motor mounts I would need and where I can locate them?


You will need Oldsmobile V-8 mounts to accomplish the engine swap you’re considering. The 1973-74 Omegas used a different front sub-frame than 197579 examples and you will need the later V-8 frame mounts for your 1976 Omega.

However, unless you already happen to be in possession of an Oldsmobile 403 cid engine there’s really no compelling reason to go out and find one of these for your swap project. The 403 engine has something of a well-deserved reputation for certain problems, including running hot, destroying cylinder head gaskets, and blowing out exhaust manifold gaskets. Though it might offend your loyalty to the Oldsmobile name, from a purely practical position you’re probably better off installing a Chevrolet V-8 instead of the 403 Olds engine.

Regardless of whether you install an Oldsmobile or Chevrolet V-8 you will need the correct V-8 engine mount parts. The engine mounts are still available new under GM part #10213125. You will need to find the correct V-8 frame “stands” used from a salvage yard or parts vendor.