Just doing some thinking here. I want to know if anyone has done this. I have an old 3310-1 holley. 780 cfm downleg booster type. I was wondering what the effects would be of installing an 850 vacuum secondaries base plate. This would require opening the main body slightly. Would this increse WOT performance and still take advantage of the high velocity air at the venturi that you don't have on a regular 850. Also thinking of the addition of annular boosters. The main goal of my idea is to make an original DZ one bad mutha. Anyinfor would be appreciated. Thanks!

750 is 1 11/16 plates and 850 should have 1 3/4 . your problem will be if the booster hangs too low , it may grab the larger plate and or stick in venturi area.. Might call someone like Chuck Nugget or Barry Grant to see if they will modify . Bet they will talk you out of it,,,If you get too large in venturi area , it may take more vacumn to pull your secondaires open,, thus you may have to work with softer springs .. Not saying it cant be done,, I have seen the 9310 Holley three bbls on 302's but they were singing and last I read , man with funny cowboy hat name Smokey ran them.

I had one like your talking about , but was straight legged. It had a secondary jet plate,850 base,horn milled,and some other "tricks". It was tempermental but worked great when tuned for the temp/humidity. Now its shafts and other parts (made for) are worn and gave me alot of fits. I just installed a 750dp that really woke up the car. Sold carb to buddy for parts. Wish the shop was still open.