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Hey, I just need some real quick clarification on setting the high-speed balance setting for the early SU carbs.

My understanding is that you set the idle airflow, bring the service screw in to 3000 RPM and then check the airflow again? Adjusting the same screws as you would at idle to maintain balance at high RPMs?

I need to be efficient before I attempt it, my neighbors really don't like the noise ;P

I just haven't seen it described in more detail then "First you balance your idle, then you set your high-speed balance"

Thanks!

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The factory service manual reccomends setting the "high speed balance" at 1400 RPM. The balance screw for the high speed balance is in the throttle shaft between the carbs. The idle balance is set with the throttle stop screws (idle speed screws), one on each carb.


The factory service manual reccomends setting the "high speed balance" at 1400 RPM. The balance screw for the high speed balance is in the throttle shaft between the carbs. The idle balance is set with the throttle stop screws (idle speed screws), one on each carb.

Got it. So it's done via the linkage between the carbs. Sounds easy enough.

Got it. So it's done via the linkage between the carbs. Sounds easy enough.

Yes, but after doing the high speed balance, go back and check the idle balance. Sometimes you need to go back and forth a few times (including the mixture) to get everything dialed in.

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