Curious if my brake booster should see vacuum from one or both runners. Typically its sourced from a common plenum, but the weber ida doesnt have that. So i could tap each runner on the manifold and tee together or run one. Ive seen it both ways. Curious about the effects....

 

For more even vacuum pulses to the booster, I personally would tee them together. I do know that on a piston engine, if you pump the brake pedal over and over with a booster line that feeds off of one runner, you can induce a misfire on that cylinder. I would imagine a single rotor would do the same thing.