Setting timing vs syncing dual carbs

[roma64]

Hi
Excuse my ignorance but with a dual carbs I understand needing to make sure that they are in sync. But also there’s a need to set the ignition timing as well is this correct? Stupid question. But every time I Google how to set the timing, it always refers me to sinking the carburetors which seems to be a different issue. Thanks

[Bruce.m]

Your best to set the timing statically (with the engine not running) first. If the timing is off, it can mess up the idle so you end up playing around with the carb to compensate.

Once you get the engine running you can check max advance using a strobe.

Then you can work on the carb tuning knowing the timing is not a distraction

[Piledriver]

The problem with Google is it has only sync'd carbs with a Uni-syn, which is essentially a mechanical random number generator.
(These go by many names, as the devil tends to do... if it has a floating ball in a tube, its a uni-syn)

Evil looks like this, amongst many other forms:

The one you want has a moving flap and an adjustable air bypass to set range, and has a dial indicator---even the EMPI ones are good, get the accessory adapter setup with rubbers seals for various intake sizes.

Empi version with rubber adapters
This also works at any angle as it has a return spring for the resistance for the air vane


You can also use a matched set of vacuum gauges or even digital or mercury manometers, but in my experience the plastic flowmeter is best.
(do not blip the throttle if you are using mercury vacuum gauges, as you will have empty mercury vacuum gauges)

[Bruce.m]

Also, if you have a very good music ear … you can do it by ear using a length of rubber pipe.

[roma64]

Thank you