Technical Olds 394 tri-power

So i bought an old Offy tri-power inane for my car, it hasn't yet arrived, I'm just impatient. The car is a 62 Dynamic 88 Convertible that i PLAN on swapping the roto10 slim jim for either a Muncie 20 or a T5, but that's not happening soon. So as I'm hoping to rock the Slim Jim for the year, what am i gonna need to make the tri-power work with thr slim jim TV linkeage?
I know speedway has kits to modify factory 2G carbs into the outer, secondary units, which is part of my plan, but can i use the factory 2bbl that i have as the center carb?

BTW, i opted for a tri-power because 1) they're cool and 2) 2x4 seems excessive and 3) factory 4bbl intakes don't have that WOW factor. AND i wanted more fuel.

Ultimately i plan on getting a new center section for the 9.3 rear end and putting some lower gears in with a posi, i don't expect to win a race, i just wanna have some fun. Show my kids how it's done

 

I would imagine your original two barrel would work fine if in good shape. Just unsure as I haven't tried it on whether the progressive linkage will easily work with the trans linkage

 

That's the concern, the progressive linkeage AND ****** linkeage

 

Your engine came with a large base 2GC. I'm not sure what carburetors the intake manifold you bought is drilled for; I've seen them for both small and large base Rochesters.

 

Good point, I'll measure the spacing on the manifold when it comes in later today

 

IIRC, some GM tri-power setups came with a large base center carb with a choke and two small base, no choke, no idle circuit, no power valve end carbs. Some had all three small base carbs.

BTW, some of the early aftermarket 3x2 intakes were drilled for three-bolt Strombergs.

jack vines

 

You've got it backwards. There were lots of factory setups with a small base center carb and large base secondary carbs ('59-'65 Pontiac for one example). Any Olds J2 setup I've seen had three small base carbs, as did 348 Chevrolets.

 

Yes, I did have it backwards. No, Maybe. In 1957 and 1958 Ponchos, the 3 Rochester carbs were all the small based version. Starting in 1959, the end carbs used were the larger based units, while the center carb remained small. The final year, 1966, Pontiac used 3 large units.

IIRC, Olds J2 was '57-'58 only. The 394"s never had tri-power.

Here's a screen grab of the 1951-56 Edelbrock with three-bolt carb pads.


jack vines

 

394 Is a lot of torque for a run of the mill T5

 

I would say to not over-think this. In the grand scheme of issues you're contending with to make this work, you have variables and constants. You have to focus on the constants.

Whether you run a progressive or straight linkage, everything is going to be based off of the primary carburetor. You can use your factory set up a benchmark, specifically the radius off of the throttle shaft centerline, and modify your new carb throttle attachment accordingly. Roto10s, and hydramatics generally, are exceptionally sensitive to TV linkage adjustment, and if you don't get it right, it's not going to shift well (not that they ever did anyway).