RE: 318 Hop Up, Heads VS NOS

From: WillTier@aol.com
Date: Sat Nov 06 1999 - 08:44:45 EST

In a message dated 11/4/99 12:17:56 PM Eastern Standard Time,
Frank.T.Holloway@KP.ORG writes:

<< The factory heads do flow well for a production truck engine. Stock form,
 the intakes flow approx. 210 CFM @ .500 lift, exhaust flows approx. 133 CFM
 from .400 to .600. Porting and larger valves on the intake can push the flow
 up to 270 CFM @ .500. Lifts much greater than .550 cause a decrease in flow
 and actually decreased to 250 CFM. The exhausts continue to increase in
 flow, even with lifts up to .650 inch. At .550 exhaust lift, flow is approx.
 175 CFM. Because of the difference between intake and exhaust, split
 duration cams are necessary (greater duration on the exhaust).
 
    Frank >>

Frank

You got to have a secret cheat book there don't you ? :-) Your knowledge of
these engines amazes me and I appreciate you sharing it with us. As I skip
through the posts deleting those of little interest I always check the author
and read all of yours. I am a more knowledgable person because of that :-)
Thanks for your contributions..

I do have a couple of questions though. How high can we reliably rev these
engines, for drag racing purposes ? I have read that over 5500 is trouble but
with the new mods I have done the power band seems to have risen and the
thing is still pulling good and I seem to be getting the most gains in
performance by running it close to 6000. I believe the MP comp, in 93
atleast, has the rev limiter set to 6500 ? The second question is to do with
the roller rocker deal again. Still have the stock rockers and have been
looking at going with the rollers. I know you are a crower fan but I have
read good about others and recently about Wolverines. They had a couple of
things (according to the article in sport truck) like a set screw to keep the
studs from loosening, precise ratios and the showed where they could be used
with the stock valve covers by drilling holes in the splash shield ? I don't
know cost diferences but the crowers seemed rather steep ?

Your thoughts on these ?

Thanks again for your input..

Bill

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