JET and power valve sizes 650 double pumper
whats in it for the moment
72 up front
78 on the rear
and if the vaccum is really at 10 psi idle in gear
you will need a 8. power valve
but like I said idle in gears read the vacuum gage
and what ever you ends up to minus 2 like
8.5 - 2 = 6.5 power valve