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I've seen those flat tappet style roller lifters advertised, kind of beveled where they make contact with the cam. I wonder though how long they will last, either wearing out the lifters or the cam itself.
A misconception about flat tappet cams is that they slide on the cam. Actually, the cam lobe is tilted, so the flat tappet lifter rides toward the side of the lobe, causing the lifter to spin, not just slide like these new designed flat tappet lifters for roller cams. I wonder about the friction and wear.
Todays oils are so much better than before, especially the synthetics. If your running a .750"+ cam, with really high pressures, then maybe there could be a problem with a roller cam/lifters and extended idling. If you run a .650" lift roller cam, with less spring pressure, maybe it would be fine.
Comparing a flat tappet cam to a roller, of similar lift and duration, expect about a 50-60 hp increase with the roller.
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"After jumping into an early lead, Miles pitted for no reason. He let the entire field go by before re-entering the race. The crowd was jumping up and down as he stunned the Chevrolet drivers by easily passing the entire field to finish second behind MacDonald's other team Cobra. The Corvette people were completely demoralized."
Last edited by Anthony; 03-09-2003 at 08:25 AM..
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