Carb tuning

64.5 TX Stang

Well-known member
I need some help tunung my holley 1946, I woul dbuy a book, but I am a bit short on cash right now. I wanted to know what the screw in the base adjusted, and then on the choke housing what that adjustment was for. I think it may help my somewhat rough idle.

Thanks,

Andrew
 
The screw at the base is to adjust fule inflow, to make it richer or leaner, I think. I adjust mine very slow, usually a half turn at a time.t The one on the choke should adjust the amount of fule that flows thru the choke. I keep mine about 1/3 open.
Steve
 
Are you talking about the allen wrench screw in the base? That will only adjust IDLE FUEL MIXTURE.

The screw on the choke adjusts fast idle speed, when you first pump the gas before starting the car, that sets the choke. Strat the car and adjust that screw to the proper fast idle speed for warm up.
 
HI AND WELCOME TO THE BOARD
First the screw in the base of the carb is for idle air/fuel mixture..
With the motor at idle turn this screw in or out to acheive best / smoothes idle. only turn it about 1/4 to 1/8 at a time a little goes a long way.. then readjust the main idle screw back to idle speed 650 to 700 rpm's. then readjust the mixture screw again. some times you have to do this process a coupel of times to get it right.... When you think your are done with this adjustment turn the mixture screw in just a hair (when you hear the idle just drop a little bit) this is called best lean mixture (per say)..

As for the choke I think you are talking about the plastic (most of the time black) part, it is used to adjust the choke for lean and rich. most of the time this does not needed to be adjusted.. But if for some reason it is out of adjustment you would lossen the three (3) screws on the outside of it (with motor off) and turn it just enouff to almost close the choke butterfly (with the motor cold) I'd say about 1/8" of closing all the way. You may need to back the fast idle screw all the way off the multi lob cam for the choke butterfly adjustment it may cause it to hang up.. after you have made this adjustment then screw the fast idle screw in till it just touches the cam. then start the car and adjust thie screw for perfered fast idle..... when the motor warms up the butterfly should stand streight up and open all the way and the fast idle screw should not be touching the fast ilde came.
PHEWWW that was a lot of typing LOL :lol:
hope this helps
tim
 
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