Alky by far...
A stock untouched 390 carb with stock Etube...
Alky a good start is pilot jet .035-.040, and main .065-.068
A .038-.040 pilot jet is going to give you a very rich idle but gives a good punch out of the hole may milk the oil, a .065 main will have head temps around 350-380*f under heavy load...
You may want to start a bit leaner say a .030 pilot and .060 main...on Alky and go up from there...
All depends on altitude and air density...
I ended up with these jet sizes from track temps, and my afr,rpm and temp gauges at home...
A stock untouched 390 carb with stock Etube...
Alky a good start is pilot jet .035-.040, and main .065-.068
A .038-.040 pilot jet is going to give you a very rich idle but gives a good punch out of the hole may milk the oil, a .065 main will have head temps around 350-380*f under heavy load...
You may want to start a bit leaner say a .030 pilot and .060 main...on Alky and go up from there...
All depends on altitude and air density...
I ended up with these jet sizes from track temps, and my afr,rpm and temp gauges at home...
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