I'm gonna jump in on this thread as the new motor in my GS455 is having similar (and maybe identical) issues with stalling out in hot weather. I have the Lectric Limited conversion in a stock distributor that was dyno'd on the motor when TSP built it. My stalling out only happens with the car in drive and only when outside temps get up over 90 deg. and the engine and engine compartment is allowed to stabilize up around 185 deg. On a cooler morning the stalling issue is not as prevalent. I have to set idle at 1100 plus to prevent the stalling in drive. Way too much for a Turbo 400 car with A/C. Here is what I've done so far and the problem is still the same: 1) Two proven good carbs 2) Two good original coils 3) Upgraded fuel system (RobbMC in tank sending unit, billet fuel filter and 550 HP fuel pump, new tank vapor vent, new vented gas cap, extra thick carb to stock manifold gasket.) 4) I've played with timing and mixture settings till I'm blue in the face with no help. So, my next step is to replace the distributor with a new MSC Pro Billet distributor borrowed from a friend to see if the LL ignition just doesn't like the factory coil and resistive coil wire that they say to use with their system. They say they've had this problem with Buick installations before. We'll see. So, comments are welcome as I've had to go through a very hot summer without the A/C. Using the A/C even makes the stalling issue worse and I'm tired of having to keep my foot on the pedal and turn the A/C off at every traffic light. I'll keep this thread updated. I hope it's not considered a hijack.
You definitely don't want to say that on a plane! Think your having the same vapor lock issue with cat piss
Not a hijack at all. Quite possibly the same issue. Mine seemed to get better with a little Vp 114 mixed in.
Ever look Into the ac idle solenoid that goes on carb ? How much the idle changes from park to drive will tell you how off the tune is
Very frustrating. I don’t know what else you can do to solve the problem and I think the thing to do is to get rid of it. I’d be willing to help you out and take it off your hands. Think about it, you’ll thank me.
Ray, you ever try throwing a set of points back in it and see if it goes away? If you have the LL electronic ignition, you should be able to remove it and replace with points, since they both use the resister wire. Possibly check the resister wire to the coil, too. Maybe it's providing too much resistance when it gets hot.
Thanks for the thought but it’s not vapor lock in my case. Note that the motor starts right back up after stalling just by tapping the starter and idles fine.
I do run only non-ethanol 93 octane gas plus a 10% mix if 112 leaded race fuel at least until I get this problem sorted out.
Not even a glimmer of possibility that I'd get rid of that GS. I'll solve the problem or redo the motor before I'd sell it.
The 1972 cars were equipped with an Idle Stop Solenoid. 1970 cars did not have it. The solenoid was there to prevent dieseling, not for the A/C. It would be great if we could add it to the 1970 engines, and use it for the A/C. Only the 72 and maybe later engine intakes had two threaded bosses to mount it.
Not for someone that knows what they're doing. They make many different solenoids. Not just original.
Stacy alluded to a tuning issue. How much rpm does the engine drop going into gear? No vacuum leaks present?
