Thread: Upgrade to vortec???

Tweet

A Vortec heads will bolt on to all Gen I small blocks, including yours. There are a ton of carbureted intake manifolds available to you. Your compression ratio will be high because the Vortecs have smaller combustion chambers, you'll likely have to run premium gas. You should throw in a cam with some more duration while you've got the old heads off. Using a very conservative cam and intake with a stock Qjet carb, Vortec heads made about 50 more horesepower in my truck. I used some dished pistons to keep the compression ratio down which lets me run on 87 or 89 depending on how I set my timing.

You won't be emissions legal because no Vortec manifolds are emissions legal. The Vortec heads do not have the exhaust crossover passage under the carburetor which so there is no way to install them without modifying the emissions system which is illegal or something. I have my first smog coming up in June, I'm hoping to slip this thing through without noticing the aftermarket heads or intake (I painted everything Chevy orange so nothing stands out as aftermarket). If it doesn't pass, I'll probably do some fancy brazing and milling on a stock manifold to install just long enough to get me through.