Guy told me a few days ago that a 283 crank will run in a 305, using slightly shorter piston rods.....making somewhere like 340ci.

Sounds feasable. Anyone here ever tried that or heard of it?

 

Sounds like this guy hasn't ever built a motor before.

A 283 has a 3" stroke and a 3.875" bore.

A 305 has a 3.48" stroke and a 3.736" bore.

283 cranks have smaller main journals than 305/350 blocks. Therefore the crank wont' work in one of those blocks without using "special" "spacer bearings", or bearing spacers. And of course would require custom pistons too.

If you were to do that, you'd come up with a 3" stroke and a 3.736" bore; CID would be 263.

Talk about spending ALOT MORE money to get ALOT LESS motor... this has got to be one of the best ways I think I've ever heard of to accomplish that.

 

Ah... Noted. Math didnt add up for me either.

 

If you're dead set on stroking a 305 you can run a 400 crank (or more accurately, a modern, new production 3.75" stroke crank, same one that makes 383's with a 350) and make a 330-338ish ci engine depending on the overbore you end up with.

Im not in any way endorsing that idea, I think it's silly for a multitude of reasons, but it can be done.