As far as I can tell Harold never put a terrible amount of velocity off the seat on his high speed designs like the Voodoo. The seat durations at .006 for the 704 are 281 on the intake and 289 on the exhaust. Probably someday someone will have decimal place behind those numbers. I can’t remember for sure what the 704 specs at .004 tappet, seems like it is 287 intake and 295. The further down to the base circle the more asymmetric’s show up though. Supposedly it has 8.33 span at .0045 or .004. Can’t recall now which it was. I have not seen quite that much, it may not all get translated to the profile from the cam grinder. I would not put any stock in the 276 and 281 like the Lunati sales literature says. I just did my first 904” dia lifter version on a 704, it is like a 704 on acid. It is a beast.
Thanks Stan. You are correct, 114 is putting the exhaust events pretty far behind. At 114 that would be equivalent to the ICL installed at 112. Lol. Which is where a lot of cheap timing sets end up after 10,000 miles when the were installed at 108. That is pretty much where I think the point of diminishing returns is for that Summit cam. Where as the cams like the Voodoo pull harder in the intake, and I think hit that DMR point 4* sooner than the symmetrical type cam. The 4 is just my guideline, I am sure there are exception to it. I was thinking the 60919 or the SPC-8 could run even more retard yet because the smaller split and less acceleration on the exhaust than the intake. But I could be wrong, haven’t looked at those for awhile.
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