Jeff, lets not bad mouth the TR8. I find it interesting you can't richin it up more. We run very rich on both 8's, mainly to make sure we don't lean out at higher rpms and to run cooler. I run rich enough that my engine builder told me to back it off and not run so rich and screw up oiling problems. Your fuel pump is fine. We just run basic puralator electric pumps and I think about 4-4.5 on the pressure gauge. Are you sure that both carbs are working properly and are balanced? I am not sure which carbs feed what cylinders, because if you look at the intake when the carbs are off, it is open at the top where the carb feed into then divide. It may be more of a timing issue, and you may not be firing at the right time. I always pull my pulgs at the end of each day to see how they look. I just think you should not have a hard time burning rich if the carbs are woring properly and the needles are set correct. I also do not think you need to go to 6,000 rpm, just makes noise and problems. I stay around 5-5500 rpm.