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Old 11-15-2006, 08:48 PM
onovakind67 onovakind67 is offline
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Originally Posted by hotrodf1
hey all,

I know this had been debated several times and I've read the posts. However, here's an interesting little tidbit.

I am using a trial version of the Engine Analyzer Pro (sweet program, BTW), and was doing some research using both my babies, a 350, 10.5:1, and a 406, 9.9:1

Started fooling with different cams and such and it would seem that a hydraulic roller with the same @ .050 duration is only worth a few HP and a few ft-lbs. talking like 10 or so in each case - the average numbers also fell about 6 HP and 8 ft-lbs, telling me that the overall torque and power curves fell slightly. So there is a slight performance advantage, even on paper. And that program does take into account friction. I compared a mild hyd. roller with an aggresive hyd. flat tappet, perhaps not entirely fair, but hey.

So let's see, a roller cam: $275, roller lifters : $450, roller cam buttom, stiff front cover etc, $50 (not to mention different pushrods) Versus a flat tappet voodoo or xtreme NRG from comp with aggresive lobes (which can get closer to a hyd. roller valve actions) for $150-175 with lifters.
Roller: $775, flat tappet $175. $500 for 10 HP hurts baby!

Get nitrous instead.

I feel raped.

Anyone else have a different take on that? Perhaps Engine Analyzer is lying to me????
I think you're lying to Engine Analyzer. You need to put real data in for the cam, not just switch the selection from flat tappet to hydraulic. You'll never get the same area under the curve from a flat tappet cam that you can get from a roller.
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