electrical system questions

[64ragtop]

Howdy, folks. I've been lurking for a few days, and now feel I can ask this group for help/advice; as well as potentially contribute same.
My li'l red ragtop was owned for 24 years by a retired air force transport pilot. He did a great job of keeping the car clean and preserving the appearance, but had some (shall we say) "interesting" concepts about wiring and such. He had the original slant 5 replaced with a 318/904, added front disk brakes, upsized the rear drums, went to 14" large bolt pattern wheels and a dual master cylinder, all good stuff!

I've been systematically finding and returning to "near" stock, such things as burned out dome light circuit, fuse block with extra circuits added to terminals that then overheated and damaged the fuse holders and the box itself, many wire splices that were twisted and taped but not soldered, lots of tape from these splices coming loose, other connectors that have come loose on their mating connectors, etc, etc. (wow, that turned into quite a litany!) Anyway, it's kept me off the street and out of trouble.

I'm a retired electronic technician and radio station engineer, so the wire part is a refreshing challenge, most of the time. I have factory service manuals in paper and on CD, so I generally know what I'm supposed to find, and understand what is supposed to be and why. Having said all that, there are a couple of things that are beyond my experience and understanding.

First, though the car runs pretty well around town, it has a severe hesitation at wide open throttle just before it wants to shift from first to second or second to third. I had thought that was caused by the single exhaust, which seems to be a bit on the light side for a 318 with a 650 Edelbrock carb and (the P.O. says) a cam a little hotter than stock. I recently added a tachometer, and now I'm thinking that the hesitation is the ignition breaking down. The hesitation starts about 3,500 RPM, and the engine will just barely get to 4,000 - 4,200. This is true both under wide open throttle on the freeway, or if I bring the revs up slowly in my parking lot. The car has been converted to Mopar electronic ignition. It has a kinda tired looking "orange box", with the five pin connector. Anyone have opinion or suggestion about ignition, or am I barking up the wrong tree (again)

Second, the P.O. installed the Edelbrock carb with an electric choke wired through a Mopar device which I assume is a choke controller. It's a ceramic rectangle with input and output terminals wired in series with the ignition controlled lead to the electric choke. I found this mounted on a bracket on the topside of the distributor bracket, just below the bottom of the air cleaner. The choke did _eventually_ open fully, but it seemed to me that the temperature sensor ought to be down near the manifold where it would have a bit of heat to sense. It also has a hole in its mounting tab that fits the bolt that secures the coil to the intake manifold, but was kinda crudely mounted atop the coil bracket. I moved it to the intake manifold, and it seems that the choke is opening a bit faster. My question, though, is: do I need this Mopar controller at all, or does the Edelbrock carb have its own controller???

Thanks in advance

Bob

[AWP9521]

It sounds to me like the Electric Choke and your Ignition problem are related. The white rectangle that you are describing sounds to me like the Ignition Ballast Resistor, it is a white rectangular ceramic device with 4 connections on it and is used to step down the voltage to the ignition coil. The Electric Choke should be directly wired into the 12V Ignition feed but not through that Resistor, if it is then change that so the Choke gets a full 12 volts and the choke will open much quicker than you have been observing.

[64ragtop]

The ignition ballast resistor is mounted to the firewall, and has the four connections you mention. My mystery device has only two connections on it, and has the words "CHOKE CONT" on it with the Mopar pentastar and the number 48750. I guess it's something the P.O. didn't know what to do with, so he wired it in the ignition hot lead to the Edelbrock choke connector. It's comin' out tomorrow and the Edelbrock gets the switched 12 volts.

I'm just wondering if the orange box is crappin out at 3.500 RPM, or if I have a distributor issue or something else.

Anyone got any ideas???

Thanks!

BC

[Andrewh]

There are a lot of orange box failures. Lots of people keep an extra one on hand just in case. You may try replacing that to check. Check for slop in the distributer, but if he converted it recently, I doubt that is the problem.

[72_GTX]

I'd fix the choke problem before looking for any other issues. The symptoms you're describing could easily come from a choke that is partially open when the engine is warm and ready for more air. Take care of the known problem first and make sure you've really solved it before moving on to other things ...