amount of vacuum advance

[Big GMC truck]

1984 GMC K1500 305
I'm getting about 16 pounds of vacuum (at idle) from the vacuum advance line. Is this the right amount of vacuum? Should vacuum increase as rpms increase?

 

[pauly383]

You shouldn't have any advance at idle for a smog motor . Advance is for part throttle cruise . You may have it on the wrong port of the carb .

 

[dyeager535]

Under load vacuum will decrease as throttle opening increases.

Doesn't really matter where it's hooked up as long as the engine likes the advance it's getting.