I know Pontiac made some inline flat heads. Cadillac made a flat head V-8. I would not be surprised if Buick and Olds made flat head sixes too, but don't know.

I once owned a '51 GMC that had a Dodge flat head motor under the hood. This one had been a frame swap and all the running gear was Dodge. Is it possible more of the frame and running gear are not Chevy?

And I need to get my two cents into the small block side bar here. I'd accept the suggestion that I love them and I've owned many of them over the years. Today three of my five drivers have 350 Chevy motors under the hood. Great servicable motors. The one with TPI can be pretty exciting.

Someone has tried almost every small block swap possible, and when you see one at a car show, it is usually just another small block. I would not hesitate to use one in a driver but I can sure imagine something more interesting for anything where lifting the hood for an audience matters.

My current motor swap projects are all using big Cadillac or big block Chevy motors.

1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble...