Thread: Abbott Racing heads

For the record porting and polishing is an art, BUT head port clean up is basic common sense.
I used to work in radiator and head shop and had a proper stone contoured to give decent curve to the upper/top roof to seat area. The bottom of the port of FLOOR should never be more than polished.
I tend to straighten the throat under the valve even with inside or smaller diameter of the valve face up to the guide. On stock SBC I raise the guide face 5/32".
So I then smooth the sharp edges and clean them up. Port matching for the most part. Increasing port volume is not real conducive to low speed torque which gets your car moving.
Forced induction does not need huge volume. Large ports are for high rpm and high speed you need a lesser volume to keep port flow speed up over volume, but this is a dance.
The valves I like to back cut with lesser angle, on 45 degree angle back cut to 30 degree. 30 degree back cut with a 15 degree. Then center up the seat riding in middle of the valve face. I like to do at least do the typical 45 seat with 30 upper cut and 60 lower. Depending on the chamber design you can also add a 15 degree cut.
Generally I like about 0.025-0.035" wide intake face and 0.045"+ on exhaust. If the face can handle it I like a nice thick face on exhaust as they have to transfer heat. A small flow variance is minimal vs longevity.
Again general clean up and smoothing does more than you think.
Oh and as for clean up use sand rolls over burrs for more control and less chance of over working a port.

Since i'm new to this site, i really appreciate the great idea's that i got from you guys. But
after talking to a few shops like ZZP and Intense i think i'm just going to leave the heads on and just change
the springs and retainers only since i'm running a turbo with a ST1 or ST2 cam. Thanks for help everyone.