1987 318 Tuning with Summit Carb

Update, for those still reading. Ignition is good. I baselined the Summit carb to out of the box specs, except for a 66 / 71 main jet. Idled pig rich and ran with mixture screws in and speed screw all the way out, and was still turning 800 RPM. So I took the .043 air bleeds and threw in the .046 air bleeds. Okay, now we are getting somewhere. Leaned it out a bit and it will die if I turn the mix screws in. Quick adjustment on those to where RPMs stopped climbing, then backed off a tad. About half a turn out each on the mix screws. Bad news. The idle speed screw is still all the way out and it's idling at 1,000 rpm.

For timing, RPM stopped climbing at 18*, so I backed it off to 16. Took it for a spin and it runs pretty good. However, it's idling at 1,000. I can turn the timing down and lower the RPM, but it would be around 12-13 degrees, and I've got the limiter plate set to 18 (with no higher option), so if I used the timing to bring the idle down I'd have a max timing advance of 30*. Not sure that's enough. Also, I can't get the idle low enough to check the timing at say, 600 rpm, to see if I've got any mechanical timing being added. So my 16 initial right now at 1,000 rpm might only be 14 initial at 600.

So, I'm tempted, and not today since I've got to pull stumps from the pond, to put in the .049 air bleeds and see if I can use the speed screw to dial fine tune the RPMs. Or, do I add wire to the idle fuel feed tubes and try to limit the amount of fuel it's getting at idle?