Posts
58
Joined
12/14/2009
Location
USA
Edited Date/Time
1/25/2012 7:51pm
When you port a head is it bad to shave down the valve guides to make them flush? I have heard either way its good or bad, that it increases air flow, but it decreases the life span and easier to snap or drop a valve. Does anyone have any info on this?
Seriously.
The answer can be yes or no (or somewhere in between for that matter)
Sometimes just cleaning up the ports will actually result in a loss of power.
You need to know if your motor requires more volume or more velocity and on which side, intake, exhaust or both.
This alone is no simple task. On top of the hard earned knowledge you need a flow bench, degree wheel, good bore gauges and a way to accurately measure port volume.
If you have the porting done, I would recommend a shop that does CNC porting.
Today's modern motors are designed well from the factory and successful port modification require laser accuracy to make gains.
There are a few of guys that do good CNC port work (Dasa in Riverside, TUFF Racing and Cosworth come to mind).
One of the guys that I was going to have do it, learned how from Dasa and he says to cut them.
The other guy I was talking to about doing them says don't cut them.
So I was just seeing what people have to say about each way of doing it to help better make a choice on who do it I guess.
Personally everyone has there way they think is better, so I guess either one wouldn't make that that big of a difference.
The Shop
DeCal Works Huge Plastic Inventory of UFO and Polisport kits.
Luxon 4-Post Bar Mounts
$189.95 - $239.95
and
sometimes
its a suck it and see exercise
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