[rotorwrench]

The only advance you got was by venturi vacuum and depending on the spring tension it worked OK but for how long. If you need more advance or want any sensitivity it's just not going to do much. Every person I've ever seen try to use one with dual carbs ends up changing it to something else. The engine overheats at the drop of a hat.

If you've had good luck with it then that's great but most folks that I've known didn't. Even the old crab was a better distributor. At least it had a centrifugal advance with a vacuum operated retard.