I have a holley 3310 on my 390 combo and need to give it a real tune..... I want to keep the vac secondary as I will be using the car on the street alot and don't want to kill my mileage with a double squirter. I bought the proform body for the vac secondary and it is a very nice piece. I also got the secondary block conversion so I can run regular jets in the back for tuning. I also picked up the accel pump cam kit and the quick change vac seconary spring kit with springs and a summit box of jets as well.

So I should be able to get this carb dialed in now and I am wondering what I should use as a baseline jet setting??? My secondaries were opening up way to soon with the light spring so that needs to change as I had very poor throttle response down low.
My combo is as follows:

318 block 4" +.030 390 cubes
9.7-1 C/R .044 quench
Iron magnum heads ported 2.02/1.625
comp HYD XE-275HL cam 231/237 duration .50 .565 lift
Hooker 1 3/4 headers 3" collector 3" exhaust to rear
Edelbrock torker 2 intake single plane
3.73 gear 8 3/4 rear
A-999 trans 2.74 low gear 2,600rpm stall
Car is 83 cordoba 3600lbs?

TIA TBF

mine works well. i have the dp version. somethings to watch for: the rear bowl on mine hit the base plate.a little filing fixed it.also the bores didnt line up perfectly with the butterflies so a little bit of slotting fixed that. jetting i would say to start with, maybe 75 primary 82 sec. my main body had jets supplied but i cant remember the numbers.

I used one on a old 750Dp and dropped a tenth. with tuning another 2 hunds. They are well worth the $$

Thanks guys.. I'll shift this post over to the race forum ... TBF