Stock 71 1600dp 34P3 SVDA won't idle without major advance

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Joined: Sat Jul 21, 2018 11:22 am

Stock 71 1600dp 34P3 SVDA won't idle without major advance

Post by TheBugMan »

I'm backing up from an earlier post because I'm starting to think some of the advice I got previously isn't 100% and before I tear this thing apart for a fourth time I'm basically trying to get some other opinions.

Bosch SVDA
Bosch blue coil
Stock engine

Distributor was brand new just a few years ago.
Coil was brand new maybe a hundred miles ago.
Car sat in the garage for about 2 years because of some medical issues.
Did what I needed to do to refresh it, pumped all the sludgy fuel out of the system, did a ton of work including a new fuel tank, soft lines, and filters it needed regardless of how long it sat.
The carburetor is a fresh rebuild by a professional maybe 100 miles ago. Because it sat for so long I still took it off the car and cleaned everything. FWIW the jets were spotless.
Fuel pump seems to be working fine because the bowl fills up nice and fast.
No reason to believe the needle valve isn't functioning properly for the same reason unless you feel differently.
Feels like I've got good spark because I'm running great at full tilt boogie.
Also feels like I've got sufficient airflow for the same reason.
Feels like it's probably not vacuum leak related because the engine is running nice and cool both at highway speed and at high advanced idle, the only way I can keep it running.
No backfiring and no real stumbling on acceleration other than the cranked advance.

The car starts and runs great at highway speed but it won't stay running at idle unless I crank the advance up to about 28 deg at idle.

Engine runs cool even at idle and the exhaust leaks of unburnt fuel.

What would even cause this? Like I'm done at this point.