Pertronix Ignition and auto distributor, compatible?

[Turbo7MN]

So I've given up fighting with the stock points system and broke down and bought a Pertronix setup. I was trying to put it in today, but had some issues with getting it in and rememberred that the autos had the 2-point distributor which was different than the single point of the manual transmission cars. I called MSA and they couldn't tell me if they were compatible or not, and the problem is there's literally not a single picture on here actually showing a Pertronix installed in a 240Z distributor, so I'm not sure if I've got it in right anyway, I can get the main screw holes lines up, but then there's another screw hole that doesn't line up with anything, and I really have no clue if it's in how it's supposed to be. I really was hoping to get this car out of my friend's yard this weekend so any insight into this would be great. In the meantime I guess I'll begin the hunt for a MT distributor.

Edited November 1, 2008 by Turbo7MN

[Turbo7MN]

Alright... 99% sure they aren't. I can see all the holes that the pertronix system is supposed to mount to, they're just in different places on the AT distributor. Since the mounting plate (the bottom part of the "contact breaker" assembly as referred to in the '73 FSM) is actually removable... it stands to reason that the MT contact breaker could just be swapped in, since really all you need is the bottom plate. When I get my hands on a MT distributor, I'm gonna give this a go and see what happens.

[DeesZ]

To the best of my knowledge Pertronix does not make a unit for the dual point distributor, so you are right, the one you have is not a fit for your application. I do not think that it is just as simple as swapping base plates, either, as there are some 'wiring' issues to be dealt with too. IIRC the 'second' set of points was there to allow for changes to the advance curve, and under full throttle there is a switch-over to them from the first set. I think if you simply swap in a single point system there will be issues of having little to no spark at full throttle. I'm running on memory here, so if anyone can verify or refute that, please do so.

Several of the members here have converted from automatic to manual shift, and I'm pretty certain that they would have run into this or related issues.

[alhbln]

Check if you can fit the round magnetic sleeve, if that fits and the distance between the sensor on the baseplate and the sleeve is correct then you can still modify the baseplate and install this kit.

The double points distributor adds a second pair of points to enable a 7º retarded timing which is enabled via a thermostat switched relay (see page EE-26 in the workshop manual).

It should be no problem to install the Pertronix setup, connect the black cable from the Pertronix sensor to (-) of the coil, and the red cable to +12V ignition (from the ignition key). You then need to setup the timining to 5º-7º BTDC at idle (fine tune to around 750-800 rpm in 'N').

The retarded switching via a thermostat was introduced to comply with exhaust regulations, as i am in europe i have no idea if this change will be a (legal) problem for where you live

Edited November 2, 2008 by alhbln

[Turbo7MN]

We have no emissions testing here in MN . No worries.

DeesZ, I have read on here about more than one instance of someone switching from the dual point to the single point distributor with any issue. And seeing as the Pertronix replaces most of the factory ignition system anyway, I'm not sure if I should worry too much about this. This car hasn't run in over 8 years and I'm quite sure it has a blown head gasket anyway... this effort may be futile in the end no matter what I do.

I'm hoping I don't regret the decision to try and fix it up as-is instead of V8 swapping it...

[alhbln]

It should be no problem to install the Pertronix setup, connect the black cable from the Pertronix sensor to (-) of the coil, and the red cable to +12V ignition (from the ignition key). You then need to setup the timining to 5º-7º BTDC at idle (fine tune to around 750-800 rpm in 'N').

)

I just had a look at the wiring diagram of a '73 manual 240Z and interestingly, the tacho is wired quite differently to what i was expecting - the tacho is inline in the +12 supply via the ballast to the coils (+) connector. To make the tacho work in the new setup, the tachos (+) connection should be wired to +12 from the ignition key (maybe even via a resistor as in the original setup), and the tachos (-) connection is then wired to the coils (-) connector.

Did anyone do this conversion and can comment on this? I'm just doing assumptions here based on the wiring diagram.

[Zealous]

Pertronix Installed on my 1971 240z. But I am 90% sure you will have to modify it to fit a dual point distributor.

[wavemux]

Turbo7MN:

Did you ever get your Pertronix installed and working? I also have an AT Dual Point setup that I would like to switch over to the Pertronix.

Thanks

Sam

[f1race79]

http://datsunzgarage.com/engine/

Page Down.

[Montezuma]

I have a 1973 automatic, I installed the Petronix in. I used a single point distro and put my dual point on the shelf. Everything works fine, my tach etc. Putting the Petronix in was one of the best low budget fixes that I did, I am very happy with it.

[cunniwj]

I replaced my AT 72 dizzy with a ZX dizzy, had no problems with tach just had to get a coil upgrade, runs great

[wavemux]

All:

Thanks for the responses! It sounds like I'm going to have to replace my dual points dizzy either way I go (Pertronix or ZX electronic ignition) Thanks again.