Ron,
Just so you don't think I am hallucinating, I dug around this evening and found one of the pics of the new CHI 4V head.
George
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It looks like a quality piece.
Michael
Michael
Hey George sorry for the late reply but I think I missed tha email. Those look like nice pieces. I did get the email from CHI and the exhaust ports are in fact smaller and intake slightly smaller but both in the same locations. I'm seriuosly leaning towards purchasing these and matching the intakes and purchasing new headers.
Ron
Ron
Huh. I'm curious just how much smaller the intake ports are? Even the ports of the cast iron heads are smaller than the intake gasket and have to be matched.
CHI has a universal exhaust port that they use on all of their heads, either a 2V or 4V exhaust header will bot up. The 2V header will obviously be a closer match in size, the 4V header will create a sizeable mis-match between port & header, not ideal in my opinion for making bhp, but can't say for sure until it's run on a dyno. Dynos have a way of proving our assumptions are sometimes wrong. I'm sure John has already done the testing on the dyno and could give an answer to that question.
This much I know for sure, the exhaust port of the cast iron head is it's Achilles heel, it requires a lot of grinding to make power above 400 bhp. The manufacturers of the alloy heads have worked those problems out so that their heads will make over 500 bhp out of the box, unported. They claim 600, but I've not read a report to verify that claim yet.
My feelings about these new parts for the Cleveland, as far as I'm concerned, they're all good. I'm glad that an engine that was at one time such an awesome competitor has not been allowed to fade away.
your friend on the PIBB, George
CHI has a universal exhaust port that they use on all of their heads, either a 2V or 4V exhaust header will bot up. The 2V header will obviously be a closer match in size, the 4V header will create a sizeable mis-match between port & header, not ideal in my opinion for making bhp, but can't say for sure until it's run on a dyno. Dynos have a way of proving our assumptions are sometimes wrong. I'm sure John has already done the testing on the dyno and could give an answer to that question.
This much I know for sure, the exhaust port of the cast iron head is it's Achilles heel, it requires a lot of grinding to make power above 400 bhp. The manufacturers of the alloy heads have worked those problems out so that their heads will make over 500 bhp out of the box, unported. They claim 600, but I've not read a report to verify that claim yet.
My feelings about these new parts for the Cleveland, as far as I'm concerned, they're all good. I'm glad that an engine that was at one time such an awesome competitor has not been allowed to fade away.
your friend on the PIBB, George