Oldbee, I am running 3.73 so I go through the ranges pretty quick, like as fast as I can for another oldbee. 4 spd.
Gary1969rr...Sounds so close my set up. 915, ported, headers, 3" exhaust, Holley 850 with dominator intake, rocker rollers,MSD ignition, cold air intake, larger dia valves, .040 over.......did a valve train rebuild with a Comp Cam Kit and chose a slightly high cam than Comp Cam recommended, but agreed it would give me what I wanted. It is a 491 cam. Looking at the plugs with recent setup showed a little more soot on the ring and darkened ceramic post. I had it at a vac of 13 which calls for a 6.5 PV, but I went with a 5.5 on advise from mechanic. So, I believe I am a little rich. When I adjust the mixture, my timing goes off so I have to find that happy medium. I have switched to ngk 4IX iridium plugs with a .035 gap. Has any one run these? Good, bad, indifferent? I have read nearly every post relative to the type of plug to use. No one particular plug recommended, but Gary, your set up is close to mine, what do you use and gap. It is a lot more sensitive than I thought it should be. Tileman61...are you saying that Holley told you to set the mixture with no power valve and then open the secondary and put in the PV? Gary1969rr....What size squirters are you using? Same in both primary and secondary? Tileman61, I am getting a feeling I am stealing your post. If I am I am sorry. I am only trying to find out what might work for me and apply it to your request.