I appreciate both schools of thought on timing - and I've known guys to go by both. The only other carbed guy in my circle of shadetree mechanics/offroaders is running a '77 F250 that be swapped a 460 with I want to say an Edelbrock 1411. This guy is extremely "by the books" in his approach - every answer to head or block questions I've ever proposed was answered with "well... take it to the machine shop".
In his setup, he goes with an 8 (sometimes 10 depending) degree advance - no testing, no questions asked, and won't go above that.
I sometimes disagree with his approach based on the fact that sometimes running parts to the shop/going by the book is not the most efficient way in the quest to "just get the damn thing running - as stable as you can with what time and resources you have".
The other school of thought which is to set it for as much as it can handle without knocking is the one that I'm leaning towards, and therefore...
New tune:
10 degrees BTDC was set to 17-18 degrees BTDC.
Idle was dropped to 650ish. The engine doesn't sound like it, but the tach wanders around about 50RPMs.
Vacuum went from 15 to 17Hg and holds steady. This kicked me back into the idle circuit, and I was able to tweak the mixture screws with a very noticeable effect when leaned out too much. I fiddled with them until I got my highest steady reading on the vac gauge.
When the vac advance was reconnected post initial timing, i was reading
about 35-36ish Hg on the gauge.
Additionally, I wired the electric choke to the ignition on the fuse box and confirmed 12v w/ the key on.
A test drive confirmed what feels to be a minor power gain - no knocking.
I assume that a vac leak is out of the question at this point.
I'll top her off this weekend and roll her down to work on Monday, then go from there. Hoping this was enough to put her onto the daily driver roster.
I cannot express enough gratitude. As stated prior, sometimes all it takes is a bit of moral support to make 'em work.
