sb tuning problems

ap6street said
sorry to sounds rude before, i dont doubt you. when the dyno place told me 1050 i asked at least 20 different people, friends and people from my facebook who constantly are racing and they all said no way. 1050 is way too big.
both carbs were brand new.

im not sure of the jet sizes. id have to take it apart.

the idle speed screw is one turn away from the engine stumbling to a stall as in turned out ? dono if that makes a difference.
idle mixtures are 1/2 turn out from fully wound in .

jets id have to open up and take a look.

850 diamond series quickfuel q
1050 race q quickfuel

So here is how to base tune a carburetor. Run idle mix screws all the way in, back them out 1 1/2 turns. Fire up the car and set idle then floats. On the floats - fuel should just wet the threads when idling. I then adjust the idle mix screws 1/2 turn either way and set them to what gives the cleanest idle. Then I set the accelerator pump usually a blue or an orange cam with a 30-35 squirter. I run a 4.5 pv in my 406 - should have an 8-10 jet spread if you are running a powervalve. If you plug it run the same jets in both the primary and secondary plates. Something in the 72-78 range primary and 82-88 secondary based on what you have posted so far should get you in the balpark with a 6.5 powervalve.

As for the idle, I usually set them high on the bench, run the screw in enough to visibly see the butterflies opened up once fired up I back them down to desired idle 800-1000 rpm.

I run 14-16 degrees initial 36 degrees total timing at 3000 rpm. Advance is all done by 3000 use one medium and one light spring.

Also check for vacuum leaks around the intake and carburetor when its cold and again when its warmed up. Spray carb cleaner around the base of the carb / intake if the engine rpm goes up you have a vacuum leak. Make sure all you auxillary ports on the carb are capped off.