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favorite this post GEM from twenty years ago(IH M, superM, 400,450 high performance cam - $750 (Lisbon,FL) hide this posting unhide

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In the sense of improving air-flow between the valve and seat, this cam is spectacular (still short duration but providing about 40% more lift at the valve) using factory valve train. Yes, about 40% more. Any of you found a cam profile to run in your antique slow running tractor engines that's 200 duration at .050 and alot more lift? BUT! this piece has more to offer than that......as if your familiar enough with your stock IH's valve timing to even be reading this add, you will know that the intake valve began opening WAY! late after the piston had began its descent down on the intake stroke. This causes problems if you come in and grind a higher lift longer profile lobe on the stock cam. Now your holding the intake valve open SO long into the compression stroke after bottom dead center that you are blowing compression backwards up through the induction system before the intake valve gets closed. If you try to advance the entire cam timing by moving the timing gear ahead one tooth....now your opening the exhaust valve WAY to early during the combustion stroke and loosing power. SOLUTION? while grinding this higher lift short duration profile on the cam I advanced the intake timing while leaving the exhaust timing alone. I have two or three of these reground cams(never installed after reground) left from twenty years ago. I was the guy that first put out the JD two cylinder cams(with corrected intake timing) in the late 80s 90s from Fort Wayne, IN . I had a couple hundred cams out there in the antique pulling circuit. Seems like one of these three cams has left-handed threads for the timing gear mount and I forgot what different model that peculiarity was for? maybe LP gas if they made one? . You can see the nose of these lobes are fairly sharp(after all the lobe must be made smaller to get more lift if your going to use the same size cam journals in the block) but never heard back from customers saying they didn't last if they were just being used for pulling/playing. Don't think you'd want these for regular field work. If interested in higher performance from your IH and doing the porting and bigger carb. work you'll need then contact me show contact info
or e-mail me on the hotmail service at bigpig41.
  • do NOT contact me with unsolicited services or offers

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