Pro form main body?

[68r/t]

Hi all, I am having some problems tuning a 750 vac Holley that I just fitted a Proform main body to.
I will give you a run down on set up and problems,
440, 9.4-1 comp ratio
Crower HDP 282 cam. 226 and 238 @ 50, 478+ 502 lift, 112 lsa
Mild ported iron heads with and CH4B intake, HP manifolds.
timing is 16 deg @ idle and 36 deg by 3200 rpm, using FBO ignition box and modified distributor.
I originally bought a new 3310 750 vac Holley as I thought it would suit a near standard 440.
From day one the thing ran really rich at idle to point the plugs were black, I drilled 2 .060 holes in front throttles blades and that gave me some idle adjustment but still rich at idle only.
I worked my way up to 75 front jets to get some color on them as they were white when I took it for a cruise with the stock 70 jets and used a Quickfuel metering plate with 84 jets in the rear but it still seemed a little lean and it slightly detonates no matter what grade fuel I run.

So I bought a 750 proform main body and fitted it today, I left the jetting the same and thought I would try it as a base line.
Idle is much better now, nice and clean and not as fumey as before but as soon as I left the driveway it was way down down on power and detonated under slight acceleration.
I worked my up to 80 front and 87 rear in the jets and it  is still detonating but is better with each jet change and am starting to get some color on the plugs as they were bone white up to these jets.
The jets seem excessive at the moment so I thought I would play with the  high speed air bleeds, as I don't have any spare air bleed jets I inserted a piece of fine copper wire (0.010 dia) hooked over in each of front and back high speed air bleeds and it is much better.

So my question really is should I go several sizes smaller in air bleed sizes (36 now) and then jet back down or do I slowly go down in air bleeds and keep the current jetting or am I totally confused and should just buy that 750 hp Holley?

There is no bogging, or surging it runs great driving normally.
I have no experience  with this type of tuning of air bleeds so any help would be appreciated.

[firefighter3931]

That seems like a lot of jet but it is what it is 

I'd try with the smaller air bleeds and keep tuning 


Ron