Head porting and polishing

Hey guys, I have never done this before, but I am thinking about cleaning up the ports and bowl area of the aluminum head I have and the combustion chambers.
my questions are these:

1. Does cleaning up the combustion chambers do anything at all?

2. How much do you polish? I have read and head that keeping a rough surface on the intake promotes air/fuel mixture.

3. Are there any tips you guys have on doing this?

Thanks for any info.

Keep the intakes rough but eliminate casting flashings if there are any. Polish the exhaust very smooth. Take the high spots off the combustion chamber. I am doing my 1st head ,cast iron, lots of work. I have about 40 hours into it already and not done yet. Good luck.

if you,ve never done this before imo you,d be better off letting a pro do it. there is a trick to it. also the tools / tooling needed to do it is expensive and special for aluminum jmo
bob

Howdy All:

Hey sting- IMHO in general,polishing the combustion chambers and piston tops is worth while and accomplishes at least two things. first, smoothing and polishing removes potential hot spots which can add to pre-ignition. 2nd, a polished surface retains heat by deflecting in back into the chamber as energy.

I have no idea how smooth or rough the aluminum casting is, but polishing it sure can't hurt.

On the ports, work in the 1st inch or so is what really counts so blending the transition from as cast to the machining in the bowl, a multi seat valve seat and thinning the valve guides are helpful.

Adios, David

Super cheap major improvement: back-cut intake valves. Use a 30-32 degree cut. Machine shop can do this in 15 mins and will cost accordingly.