Originally Posted By Thumperdart
I don't focus on idle vacuum but more cruise and go a bit below that so if you cruise at 10 inches of vacuum for example then a 7.5 or 8.5 should be close BUT you need to experiment to adjust how fast you need the enrichment to suit your needs.

I am with Dom on this .its load dependant , if you are running a high stall it will affect choice as well .i have about 4" @idle but i use a 6.5 QF pv to get drivability and tip in correct . I have a 5000 stall vert

Tex

New best ET 10.259@129.65 .
New best MPH 130.32
Finally fitted a solid cam,
stepped it up a bit more
3690lbs through the mufflers
New World block 3780lbs 10.278@130.80 . Wowser 10.253@130.24 footbraking from 1500rpm
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