I need some help/suggestions/advice from the tri-power/six pack experts out there. I have a 354 Hemi going in my 30 Coupe. It has a 6-71 blower with three Holley 4412 (2300 series) carbs on top. I currently hooked up direct throttle linkage but after talking with several others running the same set-up, lookes like I can get away with progressive linkage. I am having a hard time finding any progressive throttle linkage kits that would work with the stock throttle arms for my set-up. My carbs are spaced 5.5 inches apart which I believe is the same spacing that Ford performance used in some of there tri-power cars like the Thunderbird and such. I have thought of making my own but I can’t find anyone who makes a longer throttle shaft for my carbs. Not sure if I could adapt a factory tri-power progressive linkage to my set-up. Any help or suggestions would be greatly appreciated. Thanks
I’d probably start looking at some of the tri power stuff the factories put out. Probably spark some ideas. I’m only familiar with GM, they used Rochester carbs but the progressive linkage is brilliantly simple.
As awful as todays fuels are it is a better idea to run the straight linkage you have to keep from stagnating the fuel in the end carbs, or if you don't make sure to open the secondaries every time you drive it to prevent that. I changed my one tri power to straight linkage after finding green fuzzy shit in the end carbs. . I think too that superchargers work better without a restriction on top (only one carb working)
Why do you need a longer arm on the primary, you’ve already got a hole to give you a shorter arm on the secondary?
I'd try it as is otherwise the Google search below may give some inspiration. Here: https://www.google.com/search?clien...HZoYDEUQtKgLegQIExAB&biw=1280&bih=800&dpr=1.5
Here's an old picture off the 'net; 3x2 linkage on stock throttle arms. Rochester carbs; but same idea. Pulled off the ball stud on the center carb. Different rod ends might look a little nicer.
I just ran onto a similar situation last week. Owner hauled in his car that he had let sit for almost a year without starting. Three 97’s on a very tame small block with progressive linkage. I pulled all the carbs and I was surprised how much green looking sediment was in the entire bowl of the front carb. Center carb wasn’t too bad actually. The rear had some buildup although not quite as bad as the front. And he actually had some 97 octane fuel in it.
This the same basic setup my '63 390 6V uses, stock from Ford. It works very well. Obvious from the picture how the progressive linkage works.
Piece of steel strap bolted to the center carb using a1/4" bolt into an all thread connector to extend out the ball for the throttle cable. On the lower end it uses the ball/stud for the PG kick down linkage. The linkage to the front carb was made by pounding the round linkage flat and drilling and filing the slot. Primary throttle somewhere past 1/2 way open, ready to open the secondary's. I approximated that by looking at when 4 bbls. opened. If I have to make any ratio changes I may need to put spacers under the carbs and lengthen the steel strap. Wide open throttle.
I think Pontiac had about the best progressive tri power linkage setup from any gm make. Totally adjustable carb to carb, so I'd just get some pics of that and build from there. Either scratch build or buy with plenty of repo parts available for the linkage... ...
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