Cam and valvetrain longevity....??? low duration high lift...
#672
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https://www.youtube.com/watch?v=Y6EcyKygxTg
Just for fun...... full marine dress with Dana Marine manifolds. This was just getting it tuned. We eventually pulled it to 6500.
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#673
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https://www.youtube.com/watch?v=Y6EcyKygxTg
Just for fun...... full marine dress with Dana Marine manifolds. This was just getting it tuned. We eventually pulled it to 6500.
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#675
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I ask myself that all the time, but the question still goes further than that. This engine architecture has been around for a long time. Computer development is pretty advanced. Why does anyone ever ask 4100 or 4500? Spacer or no, if so which kind and how big? Anti reversion plates? A dozen different intake choices another dozen head choices. There HAS to be one combination of parts that works best. If I say I want a 700 hp 540 there only needs to be 1 combination of parts yet apparently from all these types of threads no one is sure what that exact combo is.
Have a number of similar units out and running for some time now.
Dart S/D, 540", RHS 320's, Comp retro-hyd-roller, 9.75:1 C.R., 2527 Edel, and a 4500 Holley. Bolt-together build, absolutely no HP chasing at all!
All off the dyno at/above 730 HP @ 6200 and 700 Torque @ 4500. Have many of these still in service after 15 years or more, not a single problem to date an any!
These are tested without any accessories however.
Thanks, Gary in N.Y.
P.S. With a change to a solid-roller, some very minor head work, and 10.5/10.75:1 C.R., we see above 775 HP/725 Torque, very similar RPM band. The RHS heads flow 375/275 @ .700" from the boxes. Just tested some recent "brand-X" heads we took on for a line, and still see just above 700. The cost on these heads is about 1/2 price!
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#676
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Do you know what heads they where?
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#677
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I wanna say, 370cc . Don't hold me to it though. It was a fairly long duration solid roller, with a decent amount of lift if I recall.
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#678
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Price difference isn't much btwn profilers and rhs. Valako is adiment about me getting the 320 profilers due to the extra thickness above the runner. We never discussed rhs but I always seem to hear and read great things about them.
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#679
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Typically, if you are going to have heads ported, you get what your head porter wants you to. Doesn't mean you can't battle alittle. LOL. IMHO.
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