i have a top end question about 2 small block chevy engines for my car ... the question is if the stock top end (heads intake etc.) tpi set up off a 1991 305engine will mate with the bottom end and block of my 1968 327 shortblock? i know its a crazy thing to ask but i like odd setups and if itd work then i can pass my state emmissions

 

It'll all bolt right up. No issues whatsoever.

Not sure how that's an "odd setup"; it's just a 327. Yerbasic typical factory SBC. If you think of that as merely a 350 with a shorter stroke, sort of the opposite of a 383, then is loses most of its "mystique", as it well should. It's really quite an ordinary thing, except that most people quit building 327s long ago, because for the exact same $$$, actually less $$$$ nowadays, you can build a 350 that will beat the 327 every time. They've largely disappeared as people have woke up and got tired of getting beat over the years. Using one you already have is one thing; but it's not a good idea to put money into the short block, since .... you'll get beat by the guy in the other lane that spent the same $$$$ on his 350 or 383 .... every time, no hesitation reservation or equivocation, no other outcome possible if all else is equal, take it to the bank.

Somebody will no doubt pop up and post the old myth about "high RPMs". Ignore it when they do. It's just a myth. When 327s were new, there were just as many low-RPM mule 327s, as there were low-RPM 305 or 350 mules in later years. RPMs are all in the induction system, not the short block.

 

About emissions, depends upon how tough they are in your state about the equipment you're using. The 327 itself is not technically legal because it is an older engine than your chassis. From a sniffer aspect, with proper cam and compression, it should pass easily.