I'm about to get my greasy hands on a holley 3 barrel from back in the day and plan on running it 31 coupe with a 428 using 10:1 comp, ported 427 heads, bored .60 over and plenty of other goodies. My question has to do with the legendary bog that goes with it i already plan on run a higher than normal stall speed conv. and have thought about putting a tigher spring in the secondaries i want to know any other ideas you guys have and any help would be greatly appreciated.
I know of one huge thing that will help. If you can find a Mr. Gasket secondary squirter kit install it and it will make all of the difference in the world !! But whatever you do DO NOT GOOGLE SQUIRTER !!! >>>>.
Do yourself a favor.... Clean it up and put it up on display in your garage as wall art. There's a reason they only made a few of them and that they stopped making them.
Whatever you do - do not install the gear drive secondary linkage and secondary squirter kit that was sold for this problem. It may have worked on the dragstrip but on the street it was an evil bitch. Work with what you have and be satisfied that it will never work as well as more modern designs. I had one of those three bbls and it was bog and haul ass - that's why they came up with all those fixes. You are gonna love the gas mileage too......
Back in the early 70's I bought a 66 Mustang 2+2 that had been owned by a PA state trooper. He had put in a mild cam and hipo heads on the 289, and added one of those things. On the street in town it was basically undriveable except if you kept it at about 1/4 throttle. After about a month of terrible drivability and about 12 MPg (who cared Gulf HiTest was 39 cents a gallon) I swapped back to the standard OEM 4bbl from a wreck. Day and night. Easier starting, better street performance, went to 20 mpg on the highway. Saved rear tires also. If you want to try it knock yourself out but have a backup on the bench.
Since you already have the 3-bbl I suggest playing with it. Not much to loose and just maybe it will work out for you. If the carb is in stock form try it as is and keep track of the various changes you make. I used several of the 950 units back in the old days and they did what they were supposed to do...haul ass...that said, the new 780 and 850 are hard to beat. If you decide to sell the 3-bbl I might be interested. .
They need a lot of cubes under them to work at all. a 428 with high compression and a lot of cam might be able to handle it. We had a 440 Magnum with a wild cam and 11:1 CR that worked great with one. As stated, though, they are like a flush toilet when it comes to gas consumption. The rear jets are big enough to poke a wooden match through! The idea of nailing it to the garage wall is a good one, too. Lots better carbs out there today.
We played with one on a dirt car years ago. It worked great, but was soft compared to a regular 4-barrel set-up. I'd say try it. No complaints on the one we have. Kevin Ooltewah Speed Shop
does yours have venturis in the secondaries or the tubes ...tubes are the bigger 3 barrel used a 3 barrel on my A >weiand tunnel 327 worked great for many yearsthen went to a dominator both liked addtional spacer even with the tunnel>>>suggest you add a spacer to help with response....adding a metering block to the 2nd side was necessary too....
The 3 barrel just never seemed that difficult to make work. I just thought that if it had only 1 accelerator pump and 1 discharge nozzle to feed the front 2 barrels and nothing to supply an immediate squirt of gas when that huge ass trap door of a 3rd barrel opened up that it needed some fuel upon acceleration. That's why I added the secondary squirters and it seemed to fix the problem. This did work for me but maybe I was just lucky >>>>.
I had good luck with them back in the day... ran them with the vacuum secondaries and also with a gear drive and a rear squirter kit... both worked OK on the track. Heck if you have one what can it hurt to play with it a while?
I've still got 2 of them on the shelf, and they both worked great (one at a time, of course) on my Pontiacs. Had to hang on when the secondary opened up...
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