Holley carb questions

[Paparazzi]

Felt that my 351W wasn't running as well as she might, so checked out the timing and carb settings. A couple of questions for the engine guys:

(1) I set the distributor to idle at a mark on the balancer that's at 12 degrees before TDC. To get the total degrees I revved the engine and was expecting to be able to read the value. But it goes further back from TDC into a region (BDC) that's not even marked. I was expecting it to go to the ADC area - is my balancer on backwards? Should I just put some tape on it that's reversed from the current markings, ie line up the 0 and just count back into the BDC zone? She's idling easily at about 1100 (stock cam and heads) and #1 plug is clean with a good vacuum reading. But I'd expect to be able to get a reading when at, say 3000 RPM.

(2) When warmed up (which this time of year in 85F heat is almost immediate) shouldn't the electronic choke butterfly be fully open - ie vertical? It goes to about 80 degrees but won't open completely. If I press down on the red plastic cam it will open fully and the idle drops and she sounds much better. But if I blip the throttle it closes up a little and the revs go up again at idle. Is this the 'fast idle' on the carb? The throttle idle setting isn't even making contact at this point I've backed it out so much. Should I adjust the fast idle on the carb?

Here the butterfly isn't completely open. The 12v feed is disconnected, but makes no difference to the position.

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By pressing down on the red cam the throttle cable is allowed to 'relax', the revs drop, and the engine sounds more comfortable. Blipping the throttle immediately closes the butterfly a little and puts the revs back up.

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