I bought one of those Procomp ready-to-run distributors with a matching coil to replace the lean-burn ignition on my 77 Chrysler, and there's something weird about it: the relationship between the location of the rotor and the "tang" or whatever you call it at the bottom of the distributor shaft that fits into the slot in the distributor drive gear is not the same as the stock distributor. In other words, there is no way to put in the new distributor and have the rotor end up in the same position as the stock distributor. At first I thought maybe the lean-burn distributor I was taking out was an oddball compared to the standard Mopar electronic distributor, but I compared it with the one from my other car and it was identical. The position of the rotor in the new distributor is almost one full eighth of a circle away from the position of the rotor in the old distributor (in the clockwise direction), so I guess I can shift the wires on the cap clockwise by one position to match the new location of the rotor. Has anyone else used one of these distributors and, if so, what did you do when you came across this situation?

Thanks!

Rotate the pump drive gear till you get it where you want it. Using a large flat screw diver turn the gear clockwise and it will come up and out keep turning a little extra and drop in till you get the position you want??

I would not move the wires...just rotate the cap to get it timed.

if the vacum advance module is getting moved one direction too much...you can move the intermeidate shaft to adjust where the rotor is pointed...

the FSM shows where the intermediate is pointed but it does not matter...as long as number 1 on the cap lines with the rotor and tdc.

I would drill a hole in the cap & check the rotor phasing (SB?). I'd set the timing marks @ ie 10 BTDC (or wherever your initial is) & line up the reluctor w the magnet & JUST moving away (CW if SB) from the magnet & see where this puts the rotor blade in relation to the underside #1 cap terminal keeping in mind that the mech adv is going to move the reluctor CW from that point and vac adv is going to move the magnet CCW from that point and that the vac adv will change the phasing & make the rotor when you freeze it w a light move CCW from it's original 10BTDC phased position.

Move the plug wires around and rotate the distributor until it fits and lines up. Your new #1 plug wire may not be exactly where you old one was, but close. I run that same dist on my 440 with no issues.

Just like some have said, you'll need to move the drive gear, i just bought this dist., i picked one of the front terminals as #1, then pulled #1 plug, bumped it over to find TDC on the balancer for #1 fire, then i moved the drive gear untill the rotor lined up with where i set the #1 plug wire, lined them up as close as possible, then clipped on the cap, snugged the dizzy up (but still moveable), hooked up the 2 wires, by-passed the ballaced resitor with a 10* jumper wire, jumped in the car, it busted right off.

Red wire too + side of coil
Black wire too - side of coil

Wow, quite a variety of answers. Since I am fundamentally a lazy person, and the distributor is already in (and it was hard to squeeze it in there, as far as I can tell the O-ring was a bit thicker than the old one), I may just try leaving the spark plug wires about where they were and see if it can be timed to run good, and it that doesn't work, shifting the wires one position clockwise to match the rotor.

Here's another potential problem, though: the engine is a 440, and since it's a late 70's New Yorker with all the options, it's really crowded around the distributor. The Procomp distributor has an integral ignition module that sticks out of the side, and it limits how much you can rotate the distributor. Here's a picture:



The shiny rectangular lump at the upper left with the two philips screws is the ignition module, and you can see with a small counterclockwise turn it would hit the corner of the intake manifold. You guys who have already installed one, is this installed right? Is it going to give me enough range of movement so it can be timed?

You do realize that it doesn't make a bit of difference where the rotor points at number one TDC firing as long as it is pointing at the number one plug wire and the firing order is followed around the cap.
The factory location is for consistnacy and easy reference.

Try it where it is. If you can't get the timing to adjust to where you want it, then you'll have to twist the distributor clockwise a bit and move the plug wires over. I had it so my vacuum cannister was further clockwise than in your pic.

Thanks for posting this so the topic can be used as a big warning not to buy any of this cheap ProCr@p junk.

I don't trust anything starting with "Pro".

Mine has set screws that you can loosen so that you can phase in the rotor.
Benn using my Pro Comp for over 3 yrs with no problems.
You can always call procomp and they will tell you how to fix your problem.

Hey, whoa, what? Set screws? I didn't see any on my distributor, it just looked like there was a roll pin holding the shaft on. Did you have a Procomp 7000 series?

I know everyone has been tossing and turning in bed all night wondering if I ever figured this out, so I thought I'd update this post.

Rather than trying to find top dead center for a particular cylinder and lining up the rotor with the wire to that cylinder, here is what I did. I made sure that all the plug wires were on the distributor cap correctly and were going to the right cylinders. Then I rotated the cylinder all the way counterclockwise (fully retarded) and tried to start it. When it didn't start, I kept rotating it about 1/8 turn clockwise (advancing it) and trying to start it. When I got to fully advanced it almost started. So I removed the spark plug wires one at a time and shifted them one position clockwise, to give me more advance. After that it started right up. (I was fully prepared to shift the wires like that 8 times to get it started if that was what it took.)

I still have to finish adjusting the timing and the carb idle settings, but it runs pretty good right now. I'm enjoying no throttle lag, which wasn't the case with my prior Lean Burn electronic ignition with computer-controlled spark advance and tired, leaking ThermoQuad carburetor (which I replaced with a 600 cfm Edelbrock Performer).

Mine is a 8000