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Reply to "Questions regarding George's 275/285 Custom Street Cam Profile"

I resurrected this thread because I was looking for a really good cam for my Clevo. But. It isn't in a Pantera. Mine is in a street/strip 68 Mustang. Now after reading all of this I like a couple things I read.
I like where George said "Low rpm performance and drivability of 351C engines diminishes quickly as overlap exceeds 62° due to their large valves; this is especially true of engines equipped with factory 4V heads. Street performance, low rpm pep, drivability and manifold vacuum all improve as overlap decreases. The exhaust valve opening (EVO) should occur at 80° BBDC or earlier to extend the engine’s upper rpm performance and to allow the engine to perform better in conjunction with muffled exhaust systems. The intake valve closing (IVC) should occur at about 70° ABDC to avoid reversion and preserve dynamic compression. Staying within those 3 parameters requires camshafts having lobe centerline separation (i.e. LSA) no less than 112°. Camshafts having a 10° difference between intake duration and exhaust duration can be timed to center the overlap event on top dead center while meeting the criteria of the two valve events (EVO & IVC). Centering the overlap event on top dead center aids low rpm performance and drivability because piston motion is almost nil from 30° BTDC to 30° ATDC (known as the “dwell” period); piston motion provides the energy making intake and exhaust gases flow where we don’t want them to. "


I also like what PanteraDoug was saying about a rumpidy rump cam making good hp for drag racing , or something to that effect.

What I would like to know if there a cam design that will satisfy both opinions.
One with the 80 degree exhaust opening 70 intake closing, 110 or 112 LSA and enough
Duration and overlap like 60-61 degrees to have a rumpidy idle yet still have some low end performance And top end pull?

I know George doesn't like lopey idles and I know a drag race cam does have a very lopey idle. Is there a middle ground cam that George can say is borderline Ok for his criteria and borderline Ok for PanteraDoug's criteria?

I guess I want it all. Is that possible? A good middle ground cam?

My car is probably more toward strip than street but still sees fair bit of street. Let's say 60% strip and 40% street to put some numbers on things.

If it matters it is a wide ratio AOD, 3000 stall lock up converter with 4.11 gears.
The lock up keeps the rpm down for street driving and freeway cruising. The stall helps it out of the hole. It weighs about 3250 without me in it.

Danford1
Last edited by danford1
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