need info on head and intake porting

[Grim]

Makes sense, thanks

[Zedrally]

Hey Ed,

What increase did you get after your port & "polish" ?

MOM

PS. Thanks for the pic's now I have a better idea of the finish required for this operation.

[Ed]

Hey Ed,

What increase did you get after your port & "polish" ?

I don't know. I just got my car running two weeks ago. The engine was a complete rebuild with several modifications besides the port & polish. I am planning on taking it to have it dyno'd to see what she puts out.

[dburgessc]

People seem to forget at times its not the increase in HP and Torque you get from any one procedure, its the increase you get from many small things that are carefully planned out and balanced with one another. When flow through engine is right and carburetion mixture is stachiometric through your engines RPM range, ignition is strong and timing is correct, proper selection of cam profile and valve size are made as well as a good cylinder head choice are made, the list could go on and on. Power and performance are a carefully balanced mix of many things working together in harmony but I better go now before I get too Zen about this and start chanting! ha ha. Anyway my point is: Yes, porting and polishing will help and will increase horsepower but how much of a contribution it makes or whether it is worth the time and effort of doing it are very debatable. However I absolutely love working on my car and would never consider time spent improving it a waste. Talk to you all later! Don.

[Zedrally]

Yes, I'm perfectly aware that many small enhancements are required for that big bit of performance increase over stock.

That however was not the question....

Perhaps I had better re-phrase to, what is the performance increase by doing a port & polish ONLY?

1%,5%, 10%???? better??????

MOM

[dburgessc]

Sorry, I was not trying to offend you with my post. Just like talking about Z's is all. Kind of curious myself about how much HP is gained from just a port and polish. Anyone out there been dyno tested before and after porting?? Don.

[Ed]

The amount gained is relative to the amount ported properly, done wrong you can reduce flow caracteristics. But to answer your question, just cleaning up the casting slag, making a smooth transition from intake runner to head to valve seat. Maybe 5-10 hp (just guessing). I don't have any dyno results to prove it.