It has been a while since degreeing the cam.........
I think I have a thread on that somewhere...
As I recall, Willhoite said they put 4° advance into the cam, and I instaalled it with no additional advance.
It degreed out perfectly to the specs when I checked..........
Heads are aluminum BTW....
a lot of people don't go through the trouble of degreeing a cam when they install it which is why I curiously asked.
Have you done a compression test to see what the actual cranking pressure is?
Excess fuel and too much residual heat (from higher compression) in the cylinder is a major contributor of run-on.
Something I've taken with me through life, my old engine builder mentor taught me. is that In a perfect world, everything works as it should. And you can get away with a lot of little things here and there, a touch more or less timing, a little less octane, maybe a little more or a little less jet. Some tweaking here and there. Lol However, none of us really live in a perfect world but the real world and that's why this rule applies. "Whatever the compression ratio is, move the decimal point one place to the right, and there's what octane fuel you should be running kid. That way, you don't screw it up." I've thrashed on a lot of engines over the years taking that little tidbit of advice and I've never burned one down yet. Lol Now do we really need to be running 100 octane in a 10.1:1 engine? No! But a good quality gas does matter and will make a difference. Anyway, all things considered the carb would be the next place I'd be digging into as discussed. but throttle stops and the like are merely a bandaid. What carb are you running? If it's a brand new carb topping the engine, take it apart and go through it. At the least flush through the idle circuit and air bleeds with some carb and choke cleaner. If it was sitting on the bench a while, clean it. I've seen carbs waaaay misadjusted because of plugged circuits and junk in them. (My 850 Demon on my big block was a prime example!) You have to open or close one thing to compensate for something wrong elsewhere in the carb. idle circuits that aren't working correctly so you open the butterflies too much to compensate for lack of idle quality and now you're uncovering the transfer slots too much and you're adding fuel from another circuit to make/keep it running. The best way to tune an engine is with a vacuum gauge, it's a sometimes time consuming process (especially with 4 corner idle circuits) but the results are worth it! And remember that initial timing needs set with the vacuum advance disconnected and plugged off. I saw it mentioned when I was reading through some of the replies that you're not sure on idle rpm and if you don't have a tach a timing light that reads rpm is a good, cheap addition to any mans toolbox. Start back at the basics and work your way around the engine, nothing worse than having a nice fresh engine that has problems. it's frustrating!