moper
Well-Known Member
Well, using your numbers, I come out with a static of 9.7, and a dynamic of 7.7:!. That's not real good. I dont really like the cam choice, not knowing much more than you posted. You dont have the static ratio for something with that duration. Also, it's in at 105? I would think that was the attempt to get you some low end. I would run a different cam myself. With a fast rate cam (I'm guessing that is one from the specs you gave) you'll need anti pump up lifters. They should be noisey. Have you called Racer (I'm guessing they cam with the cam?) and asked what the preload (it's not lash you're setting) should be. Anti pump ups are going to be noisey. It's part of the design, and they are designed to run with very little preload. Too much and the lifters loose thier abilities a little, and can cause damage. Might be worth a call. Can you get a cylinder pressure reading from it? Use a regular compression gage, get the engine hot, pull all 8 plugs, block the throttle wide open, and test each hole. If it's below 130 psi, that's your problem. I would replace the Cometics with MP .028 thick ones, and see if that helps. You should still be well out of the range of ping on pump gas. That would bring dynamic up almost .4. I aim for 8-8.2:1 dynamic for pump fuel iron head engines, and 8.2-8.5:1 on aluminum ones. My other idea would be to pull that cam and get something that doesnt look like a class rules claimer type thing.
