I disagree with the 267 comments b/c I had once seen a well rebuilt 267 in an 78-80 Cutlass doing a burnout for an entire block which sparked my interest in g-bodies at around the age of 17... It is only terrible in stock form but a guy with a garage and a lot of time on his hands could make something out of it if he really wanted to - and he could probably get 25 mpg or better at the same time while the rest of us were getting more like 17. Also, a top speed test in my 94 blazer with the 4.3 and 2 less cylinders took me to 132 mph so I suspect 2 more cylinders and a good tune could net a top speed above 140mph ... which is what the guy doing the burnout w the 267 said his car could do but I didnt believe him at the time since he had the 3 speed trans