I agree with everyone... I use the stock HB clutch in my D8 and have been getting 10-11mins pretty consistently at 200' 7mm venturi, P4, dyn 086, sidewinder purple stuff. I could eaily lean it out and get alot better mileage, but not sure if I can drive the power
I have a werks clutch Ive used and run the .9 springs on that.