ZZ4 with HEI Ignition starts good in warm weather will not start in cold weather. New HEI parts, new Elderbrock carburetor. Engine turns over extremely fast so its not battery.

No power where ? What happen's when you turn the key to the start position ? Does the starter engage an spin the engine ? Need to give better info.

Must be the choke setting on the carburetor. You might try to take the breather off the top of the carburetor and look at the center where the air intake is and see if the choke plate is opening when you turn over the engine while trying to start. If the plate isn't letting air pass try to jam it open with something clean and preferably made of plastic that won't scratch anything. If the engine starts the choke setting probably just needs a adjustment .

Yes your ignition timing could cause your car to start hard when it's cold but I think that you should check the choke setting on your carburetor. And since it's a older car i was just thinking that I doubt that you have upgraded to a HEI ignition and you are still running a breaker point distributor and your points could be worn or needs regapped. Either way i know that most people forget to set the dwell on points too which will cause the same problem the best way to set the dwell is with a oscilos

Not enough heat sink under the ignition control module inside the distributor or the module itself is faulty.

Sounds like you need to have your ecu repaired. I've seen this problem on 91-98 Grand Cherokees due to components inside the ecu slowly failing, and really acting up when the weather is colder. A good indicator as to if you have this problem is if your check engine light takes a while to light up, on the dash, when you turn the ignition on, before trying to crank the engine. If the light is delayed in your jeep, you need to repair the ecu.

It is normal for batteries to lose a good deal of their power due to cold temperatures. If you want better starting power, try using a battery charger/maintainer overnight. It should charge at no more than 2 amps. The slow trickle charging overnight will charge and warm up the battery and allow it to develop full power for a cold morning start.

The best is to turn the key on to the run position for a few seconds then back off then back to run and then start. This cycles the fuel pump and sends a good supply of fuel up to the injectors. Also do not rev the engine excessively until it has warmed up to allow oil to flow good.
Good luck, dont forget to rate.

I had the same issue with a S-10 blazer that by wiggling the key while trying to start the truck the warning lights would come on and the engine would start. We replaced the ignition switch and solved the problem.

Have a mechanic take a look at your throttle position sensor and engine idle sensor. Make him manually adjust them as opposed to just putting in new ones. It may require that you have to have a higher idle than normal. Your underlying cause is going to be that I am sure you have a lot of miles on your engine.