adjusting 3 / 2's
 

Can't seem to find any tech support for adjusting (tuning) a 3 x 2 setup with three 97's. Any help would be appreciated.
Thanks, Phil

Re: adjusting 3 / 2's
 

what kind of linkage, progressive or straight?

Re: adjusting 3 / 2's
 

Believe it would be classified as progressive. Pedal to middle carb, then linked to front and back carbs with one linkage. Should mention that it is running very rich.
Thank you

Re: adjusting 3 / 2's
 

You may find something here..

http://www.btc-bci.com/~billben/flathead.htm

Lonnie

Re: adjusting 3 / 2's
 

Progressive and the car runs on the center Carb. until you depress the pedal enough to start to open the front and rear (dumper) Carbs. The dumpers do not use their idle circuits. Straight linkage and all three Carbs work at the same time (from idle to full throttle) I would recommend the progressive IMHO. Check out the Stromberg web site (tech center) and if you can not find an answer to your questions contact Uncle Max.

Re: adjusting 3 / 2's
 

Theres a group on the hamb board of carb questions set ups etc , most are 94 carbs but set up theory is the same . I have used this groups postings many times , some of them have it figured out...

http://www.jalopyjournal.com/forum/s...-94-group.232/

Re: adjusting 3 / 2's
 

Phil, you are right to address this issue. I had a friend who ran 3x2 with straight linkage. It ran very rich to the point that it carboned up the valve seats excessively. Finally one valve top broke off due to the carbon build up and the now loose valve top destroyed the valve seat area as it careened around in there. Block was a total loss.

Re: adjusting 3 / 2's
 

Depends on on what engine modifications you have . More info needed. I run three 97's with straight linkage and have no problems.

Re: adjusting 3 / 2's
 

I, along with many others, have been running straight linkage with 3 97s for many years and thousands of miles, with no problems or ill effects. The carbs have to be built and jetted properly, usually with #43 mains and # 69 power valves, along with careful synchronization. The result is very crisp throttle response and decent (20 mpg) highway millage. Intake manifold design and manufacture can vary in performance, but the Navarro I'm using works great with straight linkage. The only negative may be slightly worse city stop/go millage v.s. running progressive linkage.

Re: adjusting 3 / 2's
 

Re: adjusting 3 / 2's
 

Wow, you guys are great. Lots of really good info. The only other engine mods are finned heads and remote coil. Right now I have to remove and clean the spark plugs about every 100 miles. Maybe I can make the adjustments and lean it down. Thanks so much.
Phil

Re: adjusting 3 / 2's
 

Wow1 Thanks for the warning. I'll try to get this leaned up before driving it much.
Phil

Re: adjusting 3 / 2's
 

The ultimate compliment!!!!:)

Re: adjusting 3 / 2's
 

Yo Max, I do run my 2 Uncle Max 81's straight.;)

Re: adjusting 3 / 2's
 

You can not really run 2x2 successfully any other way than straight.

Re: adjusting 3 / 2's
 

Uh yeah, hence the "wink".

Re: adjusting 3 / 2's
 

I agree....thanks Max. :) Oh, and my 97s came from Uncle max. :cool:

Re: adjusting 3 / 2's
 

The Carbfather speaks! Now, about that book...

Re: adjusting 3 / 2's
 

I've learned a lot from the sources suggested by you all. Thanks again. I turned the jets down on the middle carb to a very lean setting and cleaned the spark plugs. Drove about a mile to the store, returned home and removed a plug. Found it to be completely black with carbon (after 1 mile!). Would there be any advantage to disconnecting the two dumper carbs and just work with the middle one until I get the thing running right and then reconnect the dumpers? Sorry for my ignorance but this is my first three carb setup.

Re: adjusting 3 / 2's
 

When you said "I turned the jets down on the middle carb to a very lean setting" you talking about the idle mixture screws on the base of the carb?
This does not affect the main jets, these are different, and unless you have adjustable main jets, and your actually adjusting these.
What you adjusting?
Martin.

Re: adjusting 3 / 2's
 

Martin, I am adjusting the two screws on the front base of the carb. I start the engine, turn the idle screw up to get some rpm's then adjust these two screws. I turn each one in until the engine begins to run rough, then back off until engine runs smooth. But these aren't the right ones? AAAARRRRGGGHHHHHH!!!!

Re: adjusting 3 / 2's
 

I would suggest you remove and block off the two outer manifold openings and concentrate on the remaining center carb until you get the carb theory straighten out. There are a lot of tuning skills required to run multiple carbs. Get some information on carb tuning and study up a little. Might want to consider Uncle Max to help with the jetting. Once you get the single carb straighten out and some tuning skills under your belt, than add the other carbs back in.

Re: adjusting 3 / 2's
 

Would it work to just cut off the fuel supply to the outside carbs? (or remove the linkage to them?)
Thanks, Phil

Re: adjusting 3 / 2's
 

You could put blocker plates under them. It would probably work to do as you suggested, but there would be some leakage around the throttle plates, I think I would make some thin plates to block them as a temp fix.

Re: adjusting 3 / 2's
 

sounds good, thanks

Re: adjusting 3 / 2's
 

Re: adjusting 3 / 2's
 

Sorry bud, thems the idle mixture screws. To alter main jets you gotta get parts removed and swap the main jets.
Martin.

Re: adjusting 3 / 2's
 

Excellent! Thank you so much.

Re: adjusting 3 / 2's
 

Alright!!! I just learnt me somethin'. Thank you. I'm beginning to see why lots of guys with old cars just pay someone else to do the work for them. But then what would be the point of owning the old car? 3/2's are a booger but once I get this thing figured out, they'll be MY booger.http://www.fordbarn.com/forum/images/icons/icon4.gif