Thread: Detonated Dreams

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Upon further review.....

RummRum wisely sugested a differant cam because my DCR was too high. After a little research on the net i was fairly convinced this was true. I've been shopping cams to get DCR below 8.0 to be safe(current DCR = 8.6). I called the tech line at CompCams and talked to a fellow that clearly didnt want to be talking to people about cams. He said that i should be fine with 8.5 DCR. He suggested Comp Cam p#12-404-4 which is the 268H and has an intake closing(.050") @ 41*. He also said that the higher lobe seperation would help reduce knock.

How does the brain trust @ CHR feel about this?

This seems to make more sense to me but i am curious how much DCR you can really get away with on pump gas in middle america. Also, is the KB.com calculator the best one on the net?

Originally Posted by 63SSII

Also, is the KB.com calculator the best one on the net?

I don't think it's a matter of being the best or the worst. It's a matter of using the same one every time and comparing results to known other results. For instance, I have seen motors that register 8.8:1 on KB's calculator, yet run fine on pump gas without detonation. I'm of the opinion, after thinking about it for a while, that the combustion chamber design has a great deal of bearing on whether the motor detonates or not on a certain grade of fuel. The chambers in those 441 heads are pretty old technology and may be part of the problem.