Hey guys, I am fitting a 55 DCO Weber on to a 12a Bridgeport for circuit racing, has anyone any set up experience with this?

I am looking for a starting point for jet size, air, imulsion tube etc. The carb has 48 chokes we run to 9500 rpm

100 leaded fuel any ideas??

 

There is just not much data on that one. Quite a bit of carb for a 12A. With 44MM chokes in a 48 IDA will get you 310 HP at 10,700 from a big "J" bridgeport. Looking for 12 to 12.5 F/A and 1550-1570 EGT and .666

(the devils own) BSFC.



That setup would have 230 mains, 1.00 or.80 air correctors and f-8 tubes. Some serious carb mods required as well. A 350 or 400 needle seat or gross jet if you can find one. (out of production for years now) If it hase a filter above the needle seat like the IDA, discard it. The hole into the bowl from the needle seat will probably be to small and need drilled out.



Set the float high enough for the boosters to drip at idle, then lower it just until it stops. Run the highest fuel pressure the needle can control. Maybe 6-8 pounds. A large free flowing air filter allways.



The engine will not provide enough flow at low speed to develope a good depression in the carb, and it will stay over lean until the revs are way up. Over 9,000 it will start to lean because of poor fuel flow.



Using smaller chokes could get you going sooner than those monsters. It may have been set up properly when you bough it. Any chance of that?



Lynn E. Hanover

 

only cari know about with one of those was the 79 racing beat bonneville car, 55dcoe on a PP 13b engine, good enough for 180ish mph....

 

I should have thought of that. A Weber book would have a bunch of set-up data, and a call to Racing Beat might get you right on the money with the first call.



Lynn E. Hanover

 

Carb mods:

This is for the IDA Weber





https://www.nopistons.com/forums/index.php?...st&id=36309



https://www.nopistons.com/forums/index.php?...st&id=36340