well, i just got my air compressor home, so i am going to give head porting a try on a set of 416's i have laying around

i am going to gasket match the intake ports and enlarge the exhaust ports a little

what do i do about the bowl/ short side radius of things?

and what porting bits should i buy for my die grinder?

thanx for the help

 

here are the three shapes I use

search my past posts on porting 416's its all there.

 

I had a lot better luck using stones as opposed to carbide bits on the cast iron. I was not able to control the carbide bit very well and the jerking tore the iron up so I couldn't get it smooth again with the bit. But the stones allowed me to smooth those spots out and took material off. I ended up setting the 19 dollar carbide bit asside and used the stones for most of the work.

That's just my inexperienced experience. There are a lot of post about what to smooth and trim in the heads on this board but getting the feel for the tools is something you gotta practice with preferably on a spare head.

The stones also take off less material so it's harder to mess up but still does the job.