running 3x2 flathead pro/cons

Ill let you know next week! haha. ive only driven my 40 with 2 carbs so far, but now that its all broke in, and everything is fixed up, ill be running all 3 97s now, straight linkage. I will be plumbing the lines tomorrow. Ive ran it on the 3, it idles just fine. and for the record, my next flatty is getting 4x2s (and it'll be in the 245)

If you run 2 carbs, you wont be dissapointed tho. Mine was a beast on two (even tho one power valve was stuck open), so itll be interesting to see what the third does to it.

Beecher

 

flathead31coupe....let me know how running 2 or 3 94's works out for ya

 

so if i plan to to run three 94s plug all power valves,0.42 jets and progressive linkage for a start does that sound right....

 

Stock jets are typically around .050....042 would be really lean, and with no power valves you have no enrichment at full throttle. Mixture requirements at full throttle and part throttle are quite different...the reason for power valves. You can't functionally satisfy both. You might be able to plug them in secondaries if they open late so they only function when pedal is floored, but then you'd need them jetted considerably richer than stock to simulate the action of the power valves. If you simply left in the power valves and stock jets in such a case, you'd achieve the same thing...

 

thanks Bruce, another way i was told was to plug the secondaries pvs and replace the idle adj screws with 10-32x3/8 ,also outer carbs choke baffels removed, and put in .046 main jet in sec carbs, and .050 jet in the middle carb, i dont know....

 

Often overlooked is the need to use smaller accelerator pump squirters (#71's instead of 69's) for less pump shot to help with off idle bog.

 

so with this statment witch 94s would be best to get, for a 3x2 set up.. or does it really matter... the original 94 had 0.94-inch venturii, and later y-block versions had 1.0 and 1.062 venturi with a 1 or 1 1/16 cast in the side; cfm ratings range from 155 for the smallest versions to 185 for the largest. After tallying all the variations, when production ended there were at least 17 versions of the 94.

 

Been running 3 94s on my 35pu for at least 4 years,and havent touched them sence. Running a 53 merc engine stock. The center carb is a 2100 holly with a ported vac outlet for the stock dist. Out side carbs are blocked off and are just along for the ride. which is damed near every day in the summer. manifold is a Wiend and idid have to trim a little off the carbs to get them to fit. No big deal. I have gas lines going to the dummie carbs plus progressive linkinge hooked up as well. Also made my own 12-V alternater bracket and it sits up in front of carbs and looks fine. Like i said 4 years trouble free and looks COOL. I wish it had 100 more horses but you do with what ya got.--- 8-Ball

 

so how do you know what to look for with the different ones?

 

so at least i need to get one of the carbs, like the 94 model eab that has the dis vac port for a start...

 

No...that is for the evil Loadamatic, and has ports to both ported vac and venturi signal...if you use either a good Ford distrib with brake (crab) or a Chevy post type, you'll most likely want manifold vac.
What carbs do you have...markings on left side of bowl??

 

its a stock 8ba, iam getting everything togeather to do the setup, that is why i need all the info on what carbs to get and what is needed done to them, to work the best for a daily driver...

 

Best to stick with one model, if not possible one family group...8BA, 7 or 8RC are very similar, 59-21-29, 91-99 are similar.

 

If you want to run it on the street, and its a mostly stock engine, and you want reliability, consider the 49 Merc manifold and four bolt carb. Its a a bit bigger, and one carb is always easier for every day use.

 

i know where their are three 91-99 rebuilt and new shafts for 369.00 not sure if its a deal or not

 

i was sujested to do this to them and wuld be ok... was told was to plug the secondaries pvs and replace the idle adj screws with 10-32x3/8 ,also outer carbs choke baffels removed, and put in .046 main jet in sec carbs, and .050 jet in the middle carb, i dont know....let the middle carb do the choke and the idle, and set up with progressive linkage..still im not sure

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You probably don't want to use the outboard chokes, but I have heard that you hurt flow if you actually remove them.

 

gashog..You are so right about the choke plates need to be in, they direct the air down..Without, the air tumbles, bounces, swirls, whatever..
Duane.

 

Post #46...o50 is stock on may 94's; should be fine. The end carbs will be running at full throttle only, I assume, and you are leaning them far below stock on the main circuit AND removing power enrichment, which is for full throttle use??!? I would expect that to run fine as long as you don't open throttle far, and I would expect full throttle to either drop dead on power or even to stall out the engine from lack of mixture! Those carbs would be marginal at par throttle...
The power valves exist for an inescapable reason; you have to keep them OR compensate for removing them with big mains, and if you do that you need to be sure those carbs don't operate at part throttle.

 

thanks Bruce, if iam going to run the 94 what would you do to make it streetable....as far as pv,jets, ect.. i need the advice...

 

Stock jets (49?) & 2.5 or 3.5 powervalves is where I'd start

 

thanks Ernie, so 49 jets,2.5 or 3.5 powervalves in all three carbs to start.... and should i let the middle carb do the idle and the choke, but keep all three choke plates intact...

 

That's where I'd start - it'll likely need some fiddling & tuning to get sorted out well, but I think that's a decent place to start.

You want to be sure your throttle plates, particularly on the end carbs, close all the way & seal well. Screw your idle screws all the way in. Leave the plates & wire the chokes open. The plates themselves help direct airflow and several flow tests show removing them hurts flow overall. Your center carb will the be primary will all normal circuits.

 

its been said that this is not the greatest idea, to run 3x2,on a stock flatty, but i guess i need to find out the hard way

 

It's all in the tuning...

 

i have a stock 8ba with dual exhaust, and pertronix and im running the offy regular 2x2 intake with 2 94s with straight linkage, smaller jets and power valves, runs good...minor difference in performance, but if your running a flathead you're main focus isn't performance.

 

"Anything worth doing is worth doing to excess"
Hotrodding is just:
1. Doing that.
2. coping with the consequences.

Ernies suggestiond good...the strange jet reccomendations are from folks who think that each jet somehow dumps in as much gas as it did when it was single and think their bogs at full throttle are from gas...if you need to go very far from stock jetting, usually you are compensating for a problem somewhere else.

 

Hey Mate,

What's the latest with this? You end up running 3 94's?

Danny

 

i got my carbs done, will try this set up soon.....

 

C'mon mate, I'm waiting to see how they went!

Danny