As dangerous as assumptions are, I assume the "A" in your avatar is the car you are discussing and also assume you will be running with no hood. The 3X2 set up will really stand out and be worth the effort to install and tune it. Re: difference in performance: The 4 barrel will probably perform better, but you will still be able to get all the speeding and "unsafe start" tickets you feel you need with the 3X2. Find the thread started by "Dreddybear" on Holly 94 & mulitiple carb setups. Absolutely priceless info and will save you tons of grief, even if you are not running Holleys. I am running a 6X2 setup on a nailhead powered 29 coupster (no hood). I get thumbs up constantly. I even got a thumbs up and big grin yesterday from a motorcycle radar cop. Go for it.
Interesting. Yes, that manifold has low carb mount decks compared to others I have seen. I'd be really curious to know what they originally ran for a water outlet. Not knowing that, the only think I can think of if you want to run that manifold is carb spacers.
Now that I look at the pics again, it does seem like the outlet have on there sticks up higher than most. Have you tried some different outlets as well?
I ran the tri-power on this stock Goodwrench engine but I added a mild cam. It was more responsive than the Edelbrock 4 barrel that I had. I ran a stock 283 in this Model A. All carbs on both cars were hooked up.
That's an early manifold I believe. Those 2 projections on the fuel inlet side are there to take the hexagon fuel logs of the early tri-power era. No longer on the modern day repro intake. My old Fenton had those mounts. Just an opinion but I believe that someone milled those carb pads along the way. Why? I haven't a clue. I don't believe the Corvette story because Corvettes came with high rise 4 bbls from the factory with out a problem. Ford FEs had that problem but I've never heard of the problem on a Chevrolet. These are spacers that will lift each carb and eliminate the problem. It was thought to be a HP improvement but who cares? Google them. Any way I don't think your intake came this way and there is no common answer to your problem. As seen in this 1955 catalog there is no mention of a different Corvette intake.
I have been running my tripower for about 5 years now. All three are hooked up, but I have to admit that I have two open the two end carbs once a month just to get a little fresh gas in their bowls. My main problem is getting enough air into the carbs. The filters are so small they just don't do it at highway speeds. I have been thinking of switching to open elements or back to the frog mouths. Anyone else with the same issues?
I am running all three carbs. I use 2" spacers to give them a little height and use free flow air cleaners for performance and looks. They have been on my car for about 5-6 years now with no problems at all. Use progressive linkage and keep the fuel pressure to about 6-7 lbs. and you will be golden.
You must also aqauint yourself with the mysteries of carburetor synchronization, and the tools of that science. If you are going to run non progressive or progressive, the carbs need to be sdjusted so the throttle butterflies open at the same time and the same amount. This is not as critical as on mutli carb morotcycle engines because the maifold plenums will help to blend the mixture, but for best running conditions this adjust ment of the linkages with a synch tool will achieve the best level of performance from your multi carb set up. Lots of folks think this has to do with adjusting the idle mixture screws on the carbs but this is not the case, The carbs need to be adjusted at mid throttle so that all are flowing the same volume of air. So if and when you decide to jump to multi deuces, you need to familiarize your self with this process. and the tool necessary to accomplish it.
My front and back carbs don't have idle screws. They are just for dumping gas and have larger jets than the center carb. The center carb has the idle jets and you run on it during normal driving. The two end carbs come in when you dump the throttle and the linkage opens them up.
A few years ago I helped a bud build a tripower for a 350 / 350 combo with, wait for it,,, a 350 horse cam! Got info and jets from Hot Rod Carbueration, who may or may not still be in business. I JB welded the idle mixture holes and the set-up ran great. Only problem was sticking end carbs because with this set-up they close all the way. We decided a good remedy was tweeking the idle speed screws so they took the brunt of the force when they slammed shut, which was the only time they stuck. (The proper way is the new throttle blades, as they are more oblong and have a less acute angle when shut) This set-up was very freindly around town but came on like a Holley dbl pumper when opened. I think the only time you'ed give up any power would be on a motor that is in a higher state of tune and that is large displacement, and with large heads,( like the dyno'ed example presented earlier). The one drawback to this set-up is the possibility of fuel getting stale in the end carbs, but this can happen on a Holley 4bbl.
The new throttle blades are also about twice as thick as the original blades. They have to completely seal or you have a vacuum leak and that really messes up your adjustments!!! Don't ask me how I know???
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