Holley problem

I have a '66 Belvedere with a 440, 509 Mopar cam, headers and a Holley 750 dbl pump that I have replace the main body with the Proform body and jets.
The problem I am having is it seems to load-up at idle and cruise. At idle I can look into the bores and see NO fuel dripping.
One of the suggestions that was given to me was to replace the primary power valve with a 8.5 instead of a 6.5, it has a 3.5 in it now.
I am looking for help from you guys.
Thanks  

3.5? that is pretty low and will cause a rich problem, especially if you have 9 or 10" of vaccum at idle.
As far as the proform body, if you are running the jets it came with they are probably way rich.
I have the same piece and have finally got it running properly by going back several jet sizes.
71's in the front, and 82's in the rear.
I run a 7.5" power valve and the car runs awesome with a solid cam.
Doc  

Great thanks drmopar, I will try that. I know it is running real fat.
Thanks again  

Since I am kind of new to this I borrowed a friends vaccum guage and it only shows 5" at idle, then at about 2000 to 2500 rpm it was showing 12" of vaccum.
Does that indicate a different problem along with carb?  

Wow I ran the same cam in my 440 and was never happy with the bottom end power. However I had 8-9" of vaccum not 5" at idle, that sucks. I would leave the 3.5" power valve and run 72 jets in the front and 82 in the rear. I would also advance the cam 4 degrees. This will help your vac. at idle and give you some more bottom end torque. Make sure you have initial timing set at 12 degrees with a total of no more than 38 degrees. You might want to do a comp. test to make sure your cyl. are around 140-150 lbs. Any less and this cam is usless. A swap to a 284/484 would be your best bet if the comp. is any less.
Doc