A 780 is just as easy to set up as a DP, air-fuel bleeds and jets. Block the air bleed on secondary opening passage then adjust the spring to your engine. Unlike the dp that dumps a pile of fuel into the intake, overkill. 60 ft times is just a meaningless number, other then being the same every time, the one on the windshield is the only one that counts in bracket racing.

thanks for all the comments that helps

Interesting...........The dp`s can be clean n mean and even get mileage when tuned properly and don`t "dump" fuel except from the squirter to over come the momentary lean spot from the secondary butterflys opening. And 60 ft`s are meaningless?

heavy B-body, tight conv,stock size valves, low 500 l cam...low 12s easy, consistent also....ran one for many years ,,,the old standby

When I changed the gear in my rearend from 4.10 to 4.86 pro gear, the car launched way too violently, adjusted shocks and ladders and still did a 2-foot wheelie. Put a VS carb on it and it calmed it right down. More consistent for bracket racing. I think I have the silver spring in it. 42 squirter.

To answer the question, I would estimate that more than 100,000 3310s have been used on drag cars since it was introduced on the 425hp 396 in 1965. Many of these cars have been winners.

The downleg booster carb is the only 780 in the series, everything else is a 750. If you look at the boosters some of the carbs have little tabs sticking out on the outside of the booster, those were there to correct fuel distribution problems in the 396.

Holley switched to straight boosters with the 3310-2, IIRC, and that was a long time ago.

If you're after that last tenth a double pumper is probably better. If you are after consistency, like bracket racing, the 3310 can be a very good carb.

If you're looking for a strictly street carb the 80508 is a newer version of the 3310 and I believe it has better metering.

R.

I'm sure there are some 3310's going down the track in NHRA stock class since the carb came on different muscle car engines. Guys are probably running 10's with them.

I have one sitting out in the shop that I haven't used in 30+ years. It was the first hot rod part that I bought. I think I bought it back around 1978 or so but I don't remember for sure. I ran it on the 351C 4bbl engine in the '56 Ford F100 that I drove when I was in high school.

IMO a tight converter will like the vacuum carb over the D/P. The only dislike I ever had with a 3310 was actually on the street and roll racing - the slight lag before the secondaries rolled in that a D/P doesn't have.

doood you need a dp on top of a dp with a 'y' shaped manifold on top of that with two more double pumpers! Then maybe...just maybe... it will be enough fuel for your small block!