Unhappy 360 (At idle)
Should idle mixture be set in Neutral or Drive?
Richer = counter clockwise?
For the mix I get it close in neutral, turn richer and then check results in drive. That way I'm behind the wheel and can put foot on the brake.
On later vehicles, if stock, sometime the sticker under the hood says set the
idle rpm in Drive. In which case I'll do that the same way.
On a normal carb, yes, counterclockwise is richer.
When turning the screw leaner, the difference between running well and running poorly happens pretty quickly.
When turning the screw richer from best efficiency the reduction in performance is harder to detect.
So its easier to set the idle mix by working toward lean and then backing off.
Side note: Concern about hydrocarbon and CO emissions resulted in manufacturers specifiying slightly lean idle mixtures. This began in the mid 1960s.
I don't know about your particular carb. But many of the carbs used late 60s into the early 70s only allowed for very fine idle mix adjusments. They did this by various means. It's possible your carb's idle screws do not allow as much range of adjustment to the idle fuel-air mixture.
Timing 15 degrees initial without vacuum
Softer springs in distributor according to previous owner
Full vacuum advance
Use ported vacuum since you have 15 degrees at idle. Idle sounded like its in the 600 -700 rpm range. yes?
It's not surprising your engine likes lean mixture in neutral. This is because of the there's no load and there's vacuum advance providing really long lead time. When you ask the engine to work (place in gear) at idle speeds, a bit richer will stronger. Richer mixtures also burn faster. Lighting them off too early wastes energy.
Softer springs in distributor according to previous owner
Most earlier emissions era distributors already had very soft springs in them.
They also had long advances.
1979 I don't know.
You can and should explore this later.
