Yep, all 194, 230, 250 and even 292 engines interchange all years, even the oddball ones with the intake manifold cast in with the head. Yours will fit your '66 as well as any. Even the Chevy II fourbanger will fit! Saw a '62 Vette with one of those in Swift Current back in the '70's gas crunch, he claimed 40 mpg.