Uhh, no, Chevy heads don't fit an Olds block. However, if you want to put the effort into it, that 350 Olds can be made into a fairly good (understated) performer, and since you already have it in place, just rebuilding it, and not going through the extra mess of a complete new drivetrain swap might suit you. In '81, I had a '77 Olds Cutlass Salon with the 350 that blew a head gasket. When I took it apart, I just couldn't leave well enough alone, and I "warmed it up a little". I did a basic rebuild with bearings and rings - clearances were remarkably good, "niced up" the heads with a basic port and polish and new valves, installed an Erson cam, an Edelbrock manifold, and a re-worked QuadraJet 750, some Hedman headers and a true dual exhaust. What a difference!! That Olds, which was a fair runner in stock form, became a true street sleeper - - - NICE, and a lot of fun, because nobody expected an Olds to run like that one did.

Google "Oldsmobile Performance", and read to your hearts content. Here's a link to Mondello Performance, the original Oldsmobile Guru site; Joe is gone, now, rest him, but the shop is still going strong from what I understand.

Mondello Performance Products, Inc. - Oldsmobile - (805) 237-8808

On the other side of the coin, a complete swap like Tech suggests might be a viable alternative.