Originally Posted by ap72
them opening sooner really isn't going to change a lot, it'll help some, but it'll be very slight. I would also look into properly tuning your PV circuit, its the most overlooked and one of the most important. your high load tuning should be done with this circuit NOT the jets as is so often done.
I have a 6.5 power valve. I am pulling right at 20" at idle (yea, mild cam.) I have been watching the vacuum while driving. Cruising in OD i'm around 12-15". When I punch it, it quickly drops below 5 so I haven't noticed any problem with the power valve. I haven't watched vacuum with a load, only empty. I know quick fuel makes a 4 door high flow power valve. I'm not sure what I have, I never paid attention. I just checked it for tears and figured it was good. Is there another way to get more volume of fuel other than a "high flow" power valve? How would I know if I need more fuel on the power valve circuit with out an afr gauge? It doesn't feel or sound lean under load.