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By Litshoot - 10 hours ago
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While not enough time/access to work on my car i deep dive into theory to try to understand, been looking at camshafts and have a decent idea of the timing events and spec and what they do. dynamic vs static compression, overlap etc im still completely lost when it comes to power band. Ive been looking at Oregon cams and they dont provide that spec. so comparing other brands advertised information it seems to come down to witchcraft. comparing similar cams with 108° lsa, advertised lift less than .017", but powerbands jump around. looking at the isky 505 3.5-7k has 2°less advertised duration than y-292-s (2.8-6.5k) but 14° more duration at .050. add the y-302-i 3-6.8k with 1° less than the isky. That looks like isky quicker ramp rate gives more area under the curve so that dictates the powerband. But y-284-s has 14° less duration, with a higher broader powerband than isky 301300. I assume there's too many variables. Is it witchcraft until tested with a specific application? when comparing cams does a slower ramp rate help driveability while still giving some idle chop.
Seth
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By MoonShadow - 8 hours ago
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Try contacting Ted Eaton or John Mummert here. They will clear this up for you.
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By 55blacktie - 2 hours ago
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Litshoot (7/2/2026)
While not enough time/access to work on my car i deep dive into theory to try to understand, been looking at camshafts and have a decent idea of the timing events and spec and what they do. dynamic vs static compression, overlap etc im still completely lost when it comes to power band. Ive been looking at Oregon cams and they dont provide that spec. so comparing other brands advertised information it seems to come down to witchcraft. comparing similar cams with 108° lsa, advertised lift less than .017", but powerbands jump around. looking at the isky 505 3.5-7k has 2°less advertised duration than y-292-s (2.8-6.5k) but 14° more duration at .050. add the y-302-i 3-6.8k with 1° less than the isky. That looks like isky quicker ramp rate gives more area under the curve so that dictates the powerband. But y-284-s has 14° less duration, with a higher broader powerband than isky 301300. I assume there's too many variables. Is it witchcraft until tested with a specific application? when comparing cams does a slower ramp rate help driveability while still giving some idle chop. Seth
I like to think of it as more of a science than "witchcraft", but I understand what you're saying. It would be helpful to know what kind of performance you're looking for. Engine displacement, gearing, automatic vs. manual transmission, vehicle weight, all of these things should be taken into consideration when selecting a camshaft. I don't think that advertised rpm range for a particular camshaft is particularly helpful because it doesn't take into consideration all of the above. Someone who owns an identical vehicle might say he loves or hates his camshaft (more likely to say "love", rather than admit that the wrong cam was selected), but you might not agree. I will add that Ford's 57 cam, used in all Y-block C, D, and E Codes had/has 208 degrees duration @ .050 and 113 LSA.
One member of this forum installed an Isky 30133 (RPM 300) cam that has 228 duration @ .050 with 112 LSA, and he said that he would have preferred a smaller cam that makes power below 2500 rpm. Isky's advertised rpm range for that cam is 2500-5500.
Some people only care about the sound; they want a lopey idle. Some will install the biggest cam available, only to find that it runs like crap. You have to consider if your heads, intake, exhaust, and compression will work with the cam you select. Finally, in my opinion, there is no do-all camshaft; but some are easier to live with than others.
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