head porting

Anyone ever do any porting and polishing on heads? Or gasket matching for intakes and heads? Thinking about trying my hand to give the motor a bit more breathing room.
And can anyone recommend a good kit for burrs and sanding rolls?

Thanks in advance.

Gasket matching is probably the place to start, can't get in too much trouble there. Porting is a little different matter. There is a science to what to smooth and what not to touch, and if you go a little too deep you can break through the walls. I woudn't attempt porting on a set of heads I really liked or had some good money in, at least the first time.

Summit and Jegs sell porting kits.

Don

There's some great articles on head porting on the internet.
One port job on one style or manufacture of head does not translate to another and it'll surprise you as to where and how much, or I might say how little, to take out.
Intake ports don't get polished but exhaust ports do.
Carb, RPM, bore, valve size, cam profile, lifters, rockers and numerous other aspects determine the port job required
Take an old head play and see if you even like doing it

Jim

I've been reading quite a bit about the 350 Buick I have. Turns out that the valve guides are pretty clunky in the exhaust port and most of the benefits from doing any cleanup come there. Gasket matching for the intake and polishing the runners yeilds relatively small gains in flow. The big warning for this set of heads is that you can find water without too much trouble. I figure if I can just sand out the casting crud I will run out of motivation soon enough. After all, this isnt a track machine, just a street cruiser that will have a mild cam, headers, 800+cfm Qjet, 10.5:1 pistons. I just thought I'd see what I can do with some cleanup work.

Rat'l Trap said:

I've been reading quite a bit about the 350 Buick I have. Turns out that the valve guides are pretty clunky in the exhaust port and most of the benefits from doing any cleanup come there. Gasket matching for the intake and polishing the runners yeilds relatively small gains in flow. The big warning for this set of heads is that you can find water without too much trouble. I figure if I can just sand out the casting crud I will run out of motivation soon enough. After all, this isnt a track machine, just a street cruiser that will have a mild cam, headers, 800+cfm Qjet, 10.5:1 pistons. I just thought I'd see what I can do with some cleanup work.

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You're on the right track. Cleaning up the valve bowls is always a safe and worthwhile modification. Directly below the valve seats there is often lumps or mis-matches between the port wall and the seats, smoothing the transition there really has the greatest benefit to flow but don't alter the short side radius, that can hurt flow. Go easy on trimming the valve guide bosses, be careful not to nick them or the valve seats. Also a proper 3 angle valve grind job can really improve flow too.
I've always thought that polishing the runners on a street engine is a huge waste of time, especially on the exhaust as it gets coated in carbon in no time and unless you are using EFI, carburated engines will get a buildup of goo in the intakes and on the valves over time anyway....

Agreed.... I always talk my street customers out of porting. You'll never feel the benefits unless you are all out, most of the time it hurts bottom end.
A good valve job and some bowl work is all you will need..