New carb main body .

[Canadian1968]

As discussed in another post . My carb seem to be a restriction in my setup , giving me 3.5" of vaccum at wot. It was suggested to grab myself a proform 750 carb as they often flow more than advertise  . I was looking around and  see that I can buyq a proform 750 main body, that comes with adjustable air bleeds and no choke/ horn. These man bodies are identical to the oNE that would be on a complete carb correct ?  I think the no choke horn is big plus for me . As I looked at my current holley 3310 the horn is very close to the top of my filter with my drop base air cleaner installed ( maybe 1/4" ) And the openings to the venturies look like they are rounded ans shaped much better for some better flow characteristics.

[XH29N0G]

See what others say.  I think the issue is that the carb will come with metering blocks that are set up for it.  If you can set up the metering blocks then I assume building one from parts is basically the same as buying one complete.

[Canadian1968]

the proform 67101 is advertised for a holley 3310 .

[PRH]

Two things:

-If you're reading vacuum from a carb port, try taking a reading from the manifold and see if it agrees.

-3.5" vacuum at WOT sounds to me more like the vacuum secondaries aren't fully opening.
I'd swap the secondary spring to the weakest one and see if that changes the depression at WOT.

[charger_fan_4ever]

a 750 main body and a 850 base plate is what they call a 950. The proform 950 is exactly that. Metering plates im not sure.
On the cheap you could buy a 850 baseplate and have the choke tower milled off the holley.

[Canadian1968]

the test was from manifold vacuum

[Canadian1968]

I am getting rich at WOT ( 11.5 best ) and also pulling that 3.5" vaccum at 5000 rpm on the 440.  So pulling the fuel in but not enough air.  Guess the cheapest change is to look at the spring.

[BSB67]

3.5" is crazy high.  Look for another problem or a gauge issue.  Try without the air cleaner.