260z Distributor Type

[heyitsrama]

I have an issue with spark on my 260z. I am keeping the transistorized ignition system in the car as of now (totally open to removing it however). I realized that i did not have the correct wires running to the distributor, That it was supposed to have a GR/GW combo going into it. I have these coming out from the TIU under the dash, BUT apparently both of my distributor units are points type..... I assume that this means that I cannot run them? is there another way to run the system? Or should i go look for a 260z distributor? (cant find any around specifically for this car with its TIU, everything is for the other on the dizzy modules)...

 

Man 260'z have really weird wiring. 

[Jeff G 78]

Is it an early 260Z?  My late 260 distributor did not use points.

[heyitsrama]

37 minutes ago, Jeff G 78 said:

Is it an early 260Z?  My late 260 distributor did not use points.

the VIN is 019xxx, i believe the cut off for old vs new is 60000? by any chance can you take some pictures of your distributor/coil setup? Im having a hard time finding stuff online that has not been modified.. 

 

I assume there is a method to bypass the TIU? I wonder if I would be able to run just a regular points setup....

 

[Captain Obvious]

I don't think any 260 used points. I believe all the 260s (both early and late) used the electronic ignition with the reluctor pickup.

If you can't find a proper distributor, you should be able to bypass the TIU and connect the points directly up to the coil like they did for 70-73.

Another option? I haven't tried it or researched it, but I bet anything from 74-78 would work (as they're all reluctor pickup). The advance curves might not be "right", but I bet they would "work".

[Jeff G 78]

Or change it to a ZX unit.

[heyitsrama]

34 minutes ago, Jeff G 78 said:

Or change it to a ZX unit.

yeah seems like it would be a good cost/performance gain.  I need to figure out the wiring off the  harness to make this all work....

based on

It would appear that the coil gets

• BW(power from TIU)
• BL (power from ignition SW)
• L to tach

The Distributor gets that GR/GW combo, but where does it connect on the dizzy?

The points system from a 72 digram

http://www.atlanticz.ca/zclub/techtips/wiringdiagrams/72_240z_wiring.pdf

 

shows just BW from the fusebox.

then a cable from the negative to the LT on the dizzy...

that seems pretty straight forward..

 

whats reason for the interlock relay? Its sitting within the BW connection off the TIU I think the cheap replacement oil pressure sender is not working, because im not getting readings within the cabin, i suppsose i can test by grounding it, but does that not supply information to this system?

 

I wonder if i can just unplug the TIU, and go from negative to LT? the BW should be getting power still..

I tested the coil, i was getting 12v when i was in the ON position.

 

Edited February 19, 2017 by heyitsrama

[Zed Head]

I don't think that coil gets power from the TIU,  Both the TIU and the coil might get power from the same circuit though.  The TIU just sits at the end of the coil primary circuit (the wire from the negative coil terminal) and opens and closes it based on the signal it gets from the green and red wires from the distributor.  You can connect those green and red wires to any of a number of ignition modules.

Points also sit at the end of the coil primary circuit.  But points use a mechanical method, the lobes on the shaft, to open and close the circuit.  Points are kind of like a TIU inside the distributor cap.

Some thoughts that might help you figure out how to make a system work.

[heyitsrama]

We got sparkkkkkkkkkkkkkkkkkkkkkk w000000000t. Bypassed the TIU and wired the points correctly. There's no idle, there is an occasional backfire in the carb? Leads me to believe issues with the timing, or not enough fuel in the system?

I made sure the mechanical timing was spot on, perhaps the dizzy is 180 off?

[SteveJ]

10 hours ago, Jeff G 78 said:

Is it an early 260Z?  My late 260 distributor did not use points.

All 260Zs ran the TIU.

[SteveJ]

Do not overthink this. The TIU acts essentially like an overgrown Pertronix or matchbox on the ZX distributor.

Points, Pertronix, and electronic ignitions all work off the same principle. They detect the position of the distributor and close the circuit between the distributor negative and ground. That allows the coil to build a field and discharge. The electronic ignitions (TIU/ZX) require a reluctor to detect the distributor position.

@Captain Obvious once posted a nice oscilloscope capture of a reluctor waveform. Bruce, is there any chance you still have that handy?

You could replace the TIU with an HEI if you wanted to, but you would need a 260Z distributor since it requires a reluctor to operate.

If you wanted to convert the car to a ZX distributor you would need the ZX distributor mount, and ZX distributor with the electronic ignition module attached. The early ones seem to be preferred, though I'm not knowledgeable on why. The negative wire from the coil goes to the negative on the EI module. The positive on the coil gets jumpered to the positive on the EI module. @240260280 has a nice write-up here: http://atlanticz.ca/zclub/techtips/distributor/index.html.

I did the conversion on a 240Z in a very short amount of time.

[Captain Obvious]

Yup. I got it. I didn't pay attention to the polarity at the time so I don't know if I got it right, but here's what the reluctor output waveform looks like:

[Kurbycar32]

I have an early 260z, Capitan and SteveJ are right about them all using an electronic ignition. I did convert to a ZX distributor with an e12-80 "match box" and it's one of the best upgrades I've done for this car so I highly recommend it. One gotcha for that upgrade that isn't documented with the Atlantic guide is that on the 260z you need to totally disconnect that TIU. The tach wire is also different than the diagram. I recommend upgrading to the ZX distributor, skip the tach at first and come back with a tach question. I have a tach diagram somewhere on this forum

Sent from my SM-G930T using Classic Zcar Club mobile