360 correct timing

furrystump - My 12° initial is without vacuum advance (it was plugged). If I apply the vacuum advance (I run manifold vacuum not timed vacuum) at idle, it's up in the 20's (from my memory) like yours. It idles pretty good.

After running this AFR gauge for a while, I have to believe that a lot of people's cars sound lopey at idle, not specifically because of the cam, but because it is idling a bit lean (not really lean, but leaner than they may expect). For example, if I run my idle down to 12.0 AFR on a completely warmed engine, my engine idles more steady. But I lean it to ~13.5 AFR (but it is jumping all over the place at idle from 12.5 or so to 14.9 or so, averaging about 13.5), and it does sound lopey. It sounds bad *** at that AFR.

I'm not so sure that tuning it to 12.0 AFR idling in my case wouldn't be so bad, because I idle it minimally, due to traffic, and the fact that since it's not EFI it doesn't like to shoot out the driveway as soon as it fires up. But in part I tune my idle between 12.0 and 13.5 when tuning my cruise AFR. Mine is fat while cruising at the moment. I just put in an Edelbrock 1905 and still have a good bit of tuning to do. I won't take it back to the quarter mile till I'm hitting my target AFR at WOT.

So while idling at 13.5, I always get the question, "that thang got a cam in it?" My response is, "well it won't run without one, so yeah."