Inliners International Forums General Discussion Engines Chevy 261 and 250 interchangeability

Can I use a Chevy 261 crankshaft into a Chevy 250? What about the rods and bearings? Do I need to do some modifications?
Thanks a lot!

I highly doubt it. These are completely different engines. As far as I know there's nothing internally or externally interchangeable on these motors -- except that you can modify a 250 HEI/distributor to fit a 261.

The 250 is a seven main bearing engine and the 261 is a four main bearing engine, not compatable at all.

there is one thing thats intechangable, the exhaust valves are standard 1.50 inch SBC, other than that no.

Is it true for the 292 too?
Thanks everybody!