Looking for any info on jet sizes for twin 36 dcd webers on a stock port 12a. Carbs were on a 13b stock port.

Thanks

 

It's not just the jets but the venturi tubes are different too. Post what you have in jets and tubes. Webers require a special tool to remove the venturi.

 

At one time there was a good thread on this site that had a bunch of good info on these carbs. I have my twin Webers that were setup for a stock 12a on a stock 4 port 13B. It drives good but I suppose I'm not at maximum performance.

 

Main jet numbers ground off

venturi size 25/32

emulsion tubes primary and secondary F23

Air corrector jet on primary emulsion tube number ground off
no jet on secondary emulsion tube

Pump jet 70

Starting air jet 150

Starting fuel jet 100 F1

idel jet 45

 

Still looking for some help with webers.

 

I'll go see if I can't find where I wrote down the stock main jet size if that will help.

 

The 12A setup had 25/32 sized venturi, the 13B had larger ones, perhaps 28/36. RE ground off all their jet #s so you might be close to setup now. They did offer a good sized street port engine so the they varied jets depending on porting. Only way to find your jet size will be to buy a jet gauge. porting.

 

We obtained one of the Rotary Engineering Weber 28/36 DCD carburetor sets from the company back in the late 80’s. It was a 12A stock configuration to start with and then was reworked (by R.E.) for use on a 13B street port.

One set is currently running on a Rx3 open track car w/ a 13B street port and another on a daily driver 85’ FB w/ a 12A street port.

Over the years we have compiled jetting information on fourteen of these dual carburetor sets, both stock and street ported, 12A and 13B. Several of these sets are also in storage. If anyone would like setup information regarding these units, feel free to contact me.

~ M