Will throttle body intake fit a 327?

Answer 1

It depends on your heads. Throttle body was introduced in 87 which is also the same year small blocks got a new head design. The valve covers had center bolt holes instead of two bolts on top and two on the bottom. On 1986 and down the four center intake bolts were angled like the rest of the bolts. This was a pain for installation and removal because you had to use a box wrench to loosen/tighten the bolts. 87 and newer heads changed those four bolts to straight up and down eliminating the previous hassles.

All that said, you can drill the four bolt holes to an angled pattern to make them fit. I did this to my 88 Chevy truck when I installed a 73 motor but wanted to retain the TBI. When you do this, use intake gaskets to match your heads and use a little black RTV sealant around those four bolts. I did my conversion more than 5 years ago and have never had any problem.

One thing for you to consider seriously is fuel delivery. If your motor has large valve heads or any machine work done to the heads, the stock GM TBI injectors will not deliver enough fuel. I have heard of guys using a TBI from a 454 to get larger venturis and higher fuel volume.

Another problem with GM TBI and spark systems is that they won't tolerate a big cam. In fact, you can't do much of anything with cams without changing lots of other components including the PROM in the computer. As I recall the techs at Comp Cams told me that the max duration was somewhere in the 240s which is only a tiny bit larger than stock (even an RV cam is like 255 which is too much).

Choose wisely and do ALL your homework before you purchase any parts for your engine.

Good Luck.