Timing shows 12° advanced. It was at around 15 I brought it down to 12. Mechanical advance seems to work aswell. I set timing at 12 and I’m working on getting highest vacuum but the mixture screw on drivers side is really hard to turn. Any suggestions?
Moving down to 12 likely helps your hot start issue. 15 is quite a bit of timing (though not crazy) depending on the motor. Looks like you have a 350, so you should be alright. Lots of 80s motors ran with single digit advance, so you might play around with a little less base timing.
Couple of checks:
- Is the 12 with the vacuum advance disconnected? It should be. That's your base timing. If you haven't disconnected the vacuum advance (and plugged the hose) to check timing, then do it over and disconnect it.
- You said you have mechanical advance, and that's fine and good. You probably won't turn the motor too high so it's just good to know that it isn't stuck.
- Is your vacuum advance connected to ported / timed vacuum or to manifold vacuum? That can make a big difference in how the truck runs. You probably want ported on your truck unless you have a moderate cam, then manifold can help with idle and runability.
After all this, THEN set your idle speed and only THEN do you want to start monkeying with mixture (and keeping idle steady with the idle screw as you dial in the mixture)
- Finally, on the q-jet (assuming this is the same truck as your quadrabog post), be sure you get a good look at the mixture screws. In my experience, they can be hard to fit a driver to, and sometimes you think the screw is stuck when in reality you don't have your driver on the screw. If it's super stuck, I would ONLY turn the screw outward and then ONLY remove the screw and clean it up to make it easier to turn. IF you apply a lot of torque inward on the screw you can muck up the needle.
