Okay, I'm stumped. Need some help with troubleshooting / tuning. Engine is a 1987 318 (135-145ish PSI compression and 302 heads) sitting in a Ramcharger. Cam is a Summit 6900, Edel 2107 intake, Summit M2008 600 CFM carb. I cannot get this carb adjusted correctly. I replaced a worn out Edelbrock after I had a tank of bad gas. I bolted on the Summit carb, and it was idling really rich (like 10:1 on the wideband), the idle mixture screws were turned all the way in, and the idle screw was all the way out (idle was around 1,000). It had .046 idle feed restrictors in it, so I then threw in .043 idle feed restrictors in all four corners, and those leaned it out to 13:1. But, the idle mixture adjustment screws still are all the way in, with the idle at 1,000 rpm, vac at 16. The idle adjustment screw is still all the way out and not contacting the stop. The secondary butterflies are adjusted to where the transfer slot is barely showing (it looks like a tiny square). Timing is set at 14 degrees with the vac disconnected (there's a limiter plate in the dizzy and I'm running an orange box). Floats are adjusted. No fuel dribbling out in the primaries or secondaries and the power valve is new.
I've checked the top of the intake for vacuum leaks and sprayed the hoses with water, propane, and carb cleaner, just to be sure. Can't find anything. If this sounds like a vacuum leak maybe I need to pull the intake and start over. I just had it off, but cleaned it well and then used gasket shellac to on the gaskets. Wonder if it's leaking from the bottom of an intake runner? The heads haven't been milled and I don't think the intake has been either.
Timing? I think it will take more initial as the RPMs will climb if I go to 18. Haven't tried any more than that. I checked the balancer about a year ago and don't think it's slipped.
I can also pull the carb and try the secondary adjustment again. Maybe it's getting too much air through the secondary transfer slot?
Thoughts?