Lend me you ears

In my experience, my solid lifter slantys all liked to be a bit ticky; when they get quiet, bad things happen. Yours sound just right.
Even a couple of thou too tight on the intakes will affect the idle. None of mine have liked the .010 intake/hot spec. Mine would idle there but it took extra throttle to get the same idle-speed, and then the blades were up too far on the transfers. Then it gets hard to get the carb right. Then when I make her work hard and the head gets warmer, it all takes a dump. And since it gave me no more power, nor less, seat of the pants; I settled on 13/23 at about 70*F. And then it goes all year without adjustment, sometimes several years.
My last slanty car has become my emergency back-up car. I've had her since 1994. but she hasn't been registered now for at least 4 years. Engine still runs great, but her body is returning to her native state. I warm her up, and move her around the yard whenever the mood strikes me. But the front tires don't hold air anymore, so it's getting moved less and less every year. But it runs and drives too good to be scrap........