This one is the Standard vac sec. 600 cfm, I modified it with an adjustable vac sec from QuickFuel. Worked great. I had to decrease the main jet one size. This carb is now on a 350 SBC in a Ford Model A coupe Hot Rod Before After And I used a screw as sec throttle stop to adjust a better idle.
This is my favorite "Holley", AED 650 HO With K&N Substack with 2 1/2" spacer, first in 4 hole, second is one with a divider. Here you can see that I modified the high speed air bleed to changeable bleeds, from AED this version comes only with screw in idle air bleeds. The carb was way too rich when I got it from AED. I decreased the mains one size, the IFR is now .032, the high speed air bleeds are now .033 and idle air bleeds are .069. I also switched to a 50cc acc pump, Squirter size is 37. This carb is on my 408HP 355 SBC. I tuned it with a O2 sensor. I had a 600 DP before that carb, it was good, but I had the feeling that there is more power and better tuning issues with the AED. I was right.
yes , the AED stuff seems to be pretty good . their replacement DP 4 corner metering blocks look fine and are like $46 each at summit . small stuff good too . keep some in stock . I've been using the quick fuel adjustable vac sec's on quite a few carbs , even just basic stock oem spec stuff . check part# 63-11 , $24.00 @ summit . same just not shiney . a new vac diaphram is gonna cost ya almost $10 when rebuilding so you are only spending an extra $14 . plus no spring changing . or buying . a little cap screw bolt works slick for the sec throttle blade stop .
