Re: 27 degree initial timing?
look at the cam. I think your timing settings were an attemot to get it to run better at low rpm, and that lessor settings would make it worse.
I agree. I have the exact same issue. I beat my head against the wall for a long time, for nothing basically.
The cam I run doesn't have a radical profile per say, but cars that ran this cam in the 60's had 11:1 compression. I have 9:1. Because of the overlap & the lower compression, I have to bump my timing to 22 initial, idling at 900 RPM's with 6-7" of vac.
Yeah, low RPM driving is not great, but once she starts to wind up, look out.
I tried everything at first, manifold sucking air? No! Cam grind wrong? No!
Bad distributor? No! Went thru 3 carbs, 4 distributors & 3 intakes.
The car wants to live at 22 initial and idle at 900. Being a 4 speed car it's not a big deal with converters being an issue.
I've left her alone and flog her hard. Motor has never given me problems, even on 10 hour drives.
But she has bent 1 set of axles, bent 1 driveline & tweaked a leafspring. LOL
67 RS 327, 4-speed, posi, done.
67 Modified, 454, TH-400, posi, under construction.
67 SS 396, 4-speed, basket case.
72 RS, sitting, partially done.
55 210 post, 2 door, 327 4-speed runs good.
55 2 door post, gasser project
69 Cadillac ElDorado
69 4x4 suburban
Some mornings, it's just not worth chewing thru the leather straps"