Here is a "do it yourself" guide to porting and polishing your heads . After learning how expensive it was to have it done, but also learning that it should be done to get the max flow out of the heads, I decided to take on this tedious job myself. I found this guide to go by. I figured that since I have a die grinder, compressor and workbench..why not ? I'm guessing that in one weekend I can have my "781" heads ported and polished in addition to the 2.19/1.88 valves I had installed. :eek:
Did someone say "breathe" :D
http://www.sa-motorsports.com/diyport.htm

Bought their kit and am giving it a go myself right now. Pics below...

Great info! Thanks for posting it.

Originally posted by 69CamaroSS:
Bought their kit and am giving it a go myself right now. Pics below... Glad to hear it (no negative responses so far).
Those heads cleaned up nicely.
I'll be posting some pics to my website as I go thru this "sub-project" of doing the heads. graemlins/waving.gif

In general, it looked like pretty good info to me, but I noticed a couple points I would disagree with. (or at least should be clarified)

1. Don't port match the port entry to an intake gasket. Match the port entry to the intake manifold. If you open up both the cylinder head and the intake to match a particular gasket you end up with a "bulge" in the runner that hurts velocity. If you are going to mess with the port entry, work on reducing the size of the pushrod tube bulge - that is where the restriction an SBC head is IMO.

2. Be very careful about messing with the short side radius. Yes, remove casting flash, but don't just grind away at the short turn until its rounded. A fairly sharp drop off from the port floor actually helps air make the turn.

Although I didn't see it mentioned, I personally believe that raising and widening the roof of a port is the best way to gain airflow. Raising the roof (and the bowl) is almost always better than lowering the floor.

Port bias is important to help generate swirl too. Basically the side of the port that aligns to the outside edge of the cylinder should be wider - this increases velocity on the outside of the port and induces swirl.