Cutting heads

[Carmine]

Hi everyone. When cutting heads, would that affect the intake lining up properly for bolting or the runners?? Create any vacuum leaks?? Just wondering. Thanks, Carmine.

 

[MRHP]

Yes Carmine. A large cut changes the intake fitment. The heads can be angle cut to help alleviate the problem. The intake can also be shaved to tune up the fitment. Then you also have to check the fitment of the distributor gear to cam gear as that changes as well. Lots of stuff to consider.

 

[Don Jacks]

Brian's right.These issues only happen once the total cut exceeds about .045 on a small block.

 

[427John]

This isn't unique to W's but applies to most V type engines to some degree, depending on the cylinder bank angle and whether or not its a conventional 90 degree head surface or a plank head engine that has a different deck angle.

 

[boxerdog]

I did some whacking on a BBC (deck, heads, intake) recently and used the formulas from this website to do all of the calcs:

Wallace Racing Calcs

With a little help from a skillful machinist, everything fit like new or better!

dc

 

[Carmine]

Yes Carmine. A large cut changes the intake fitment. The heads can be angle cut to help alleviate the problem. The intake can also be shaved to tune up the fitment. Then you also have to check the fitment of the distributor gear to cam gear as that changes as well. Lots of stuff to consider.

Thanks everyone for the responses. Several years ago, I was helping a friend put back together a sbc 350 which he had some machine work on. Bolted the heads on and then the intake was next. It was a stock cast iron intake and the holes in the intake and heads, weren't lining up properly. They were just slightly off, enough to make it an issue. If I recall correctly, he had to slightly raise the intake from the heads to get the bolts through the hole and started properly. Could never figure out why and then one day he mentioned something about having the heads shaved/surfaced??? I didn't give that much thought either because I didn't think it would affect anything. Now I know better. We didn't check anything else and the engine went back together and ran nicely. Guess we got lucky on everything else. True barnyard mechanics lol, Carmine.