Yo, why you didnt tell us about your engine problems?? what is your midrange screw setting? based on your description, it should be not flush with the carb but turned out by 15-30mins provided your engine is not hand modified. If it is, turn in by about 5 mins and try again, if still cannot idle more than 15 secs, then try maybe 1-2mins. I think if it can idle more then 10 secs, it should be alright. FYI, during the last nova race, my engine could only idle for 10secs coz I was using #7F. Works superbly when the engine is running at high speed. If you feel that your car will flame out after idling for a few seconds, pulse your throttle when you want to drive it. I do that during the start of a race. pulse it quickly for about 2 secs so that it doesnt flame out. Need more race tips?.....