Michael, We had some carb issues with Bubba's car (grey GT), mixture was good, EGTs spot on, but it had dead spot right off throttle then picked up, I used to immediate response. he had alot of issues, he still had crankcase evacuation tubes hooked, I'll have him get rid of that crap, and he using biased spring needles, I at some time will convert the carbs to solid needle, Joe makes a simple bushing for this. If none of that works, then I may use oil in the dampners, something I normally don't use in race carbs, I wanted to try oil at CMP, but his cas didn't have dampner rods on them, so oil wouldn't have done any good. ON the last set I built, I installed SL needles, at Davids Headley's recmmnedation, it will will be spring be fore the custoer gets out to race, so the verdict is stll out there. It's a 1800 13.0 to 1, so I guess your needle requirements may be alot different than mine, but there they are FWIW. Kent prather would be a good source of info as well. DO you have SGTs gauges, if so what numbers did you see at WOT.