Pertronix Ignitor 1761 install and coil evaluation

[akorna]

Decided to go for the Pertronix Ignitor after installing a remanufactured stock dizzy from Autozone. I had all new ignition components now, so the baseline would be a properly functioning point system. There was also some debate on the correct/best coil to use with the Ignitor – a 1.5 Ohm with external 1.6 Ohm resistor, or a 3.0 Ohm coil without a resistor. The factory set-up uses the external resistor that is bypassed during starting to deliver higher voltage to the coil/points and through the external resistor while running to protect the points/coil.

Many folks have gone through this, but I thought I'd go through my install as shown in pics below:

The Ignitor 1761 only has a five parts – the unit with leads, the cylinder that fits over the dizzy shaft (DO NOT REMOVE THE GREEN TAPE), and three screws.

1. The leads are too short to reach the coil/resistor in the stock location – you will need to cut off the ring terminals and add 8-12 inches of wire. The instructions say to use 20 awg wire – I had some 16 awg in black and red, and spiced the additional wire by soldering the joints and sealing with heat shrink tubing. I used female quick disconnects with shrink tubing to match the factory connections.

2. Before installing I would start the car and warm it up a little bit – not so hot as to burn you as you work, but enough to make sure everything is operating, and the car does not have any unexpected no/poor start problems.

3. You do not need to align the dizzy to TDC or anything like that – just pop the cap and go to work. Remove the points assembly and the plastic insert in the cut-out that connects the black (-) wire from the coil and the condenser to the points. The condenser is not needed for the Ignitor, but I left it attached in case I wanted to return to the points set up for any reason. The wire to the coil is disconnected also, but not removed for the same reason.

4. Install the Ignitor just like a set of points – you may have to rotate the adjusting screw on the breaker plate so that the two attaching screw holes align. Then reconnect the distributor ground wire with the slotted screw. IMPORTANT: The slotted screw provided is too long – if you do not add washers (none provided in the kit) it will interfere with the operation of the breaker plate vacuum advance – I made this mistake and it resulted in a poor start/poor running situation. This may be a problem others experienced with the Ignitor, but did not realize it.

5. Route the wires out through the dizzy body cut-out and make sure that it they will not contact the rotor or shaft. Press in the rubber grommet so it fits snugly.

6. Align the black cylinder over the shaft cam and carefully press down on the shaft – if you aligned in properly you will hear/feel it seat. Once in place it should almost be touching the ignitor. If it is touching, something is wrong with the install, or the dizzy is worn excessively.

7. At this point I would check the operation of the vacuum advance with a hand held vacuum pump to make sure there is no problem as noted in step 3. The advance should start moving the breaker plate at 4-5 in Hg, and smoothly return when the vacuum is released.

8. INSTALL THE ROTOR – the Ignitor just replaces the points and condenser. Make sure that wires will are not touching the rotor.

9. Install the cap. Make sure you are not pinching any of the Ignitor wires.

10. If you are using the stock coil and resistor, connect the Ignitor RED wire to the ignition input side of the resistor (Black/White wire) using your connector of choice. You will now have the red and black/wire connected to the rear terminal of the 1.6 Ohm resistor.

11. Connect the Ignitor black wire to the (-) side of the coil and you should be good to go.

12. Cross your fingers and attempt to start the car as you normally would. If the engine doesn’t start, re-check all of your connections.

13. Assuming the engine is now running, you should check your timing with a timing light, you will probably have to adjust it. You may also have to adjust carbs, open spark plug gap and other tweaks to take full advantage of the ignitor.

A TALE OF TWO COILS:

I bought two coils to test for my Ignitor install – the Pertronix 40511, 3.0 Ohm that the manufacturer recommends (bypass the stock resistor) and the 40011, 1.5 Ohm for use with the resistor.

I used the 1.5 Ohm/Resistor set-up first with the Pertronix. Subjectively, I did not sense a dramatic change in cold start/hot start, idle and acceleration over my refreshed point system (I had already tested the point system with the 1.5 Ohm coil with a fresh 1.6 Ohm resistor and did see some improvement over the apparently tired Bosch RED coil).

I swapped the in the 3.0 coil w/out the resistor. I did a cold start this morning – this is a way I’ve been monitoring progress; how many 5 second attempts it takes to start (when I first got the car in December, it took 10 or more attempts to start!) – and at 36 degrees it coughed on the second attempt and started on the third. About eight hours later this evening at 44 degrees, it started in on the first attempt. All attempts were with full choke applied. The next day, temp at 42 degrees, it again started on the first attempt. I noted a more consistent idle and smoother acceleration - not dramatic, but noticeable.

The tachometer worked fine with the 3.0 Ohm Coil. Overall, the 3.0 coil seemed to work at least as well as the 1.5 Ohm coil w/resistor, perhaps a little better – maybe the tech folks at Pertronix knew what they were talking about. Here is the final wiring diagram.

[steve91tt]

very nice write up. Thanks!

[Mikez73]

Very good. I'm replacing my 240 distributor with a new 280zx part but if I had gone with the Pertronix unit I'd surely be using this writeup.

I know you're loving that cold start improvement.

[akorna]

Mikez73,

I considered the 280zx dizzy route, but from a cost (initial and component replacement) I decided to go this route. The remanufactured dizzy was $55 from Autozone, the Pertronix Ignitor was $69 - so I had a "new" dizzy for $124 that I could convert back to points if needed. Some folks still have some luck using a salvage yard 280zx dizzy, but I didn't want to replace a 38 year old electrical/mechanical part with a 29 year old one.

The car is performing better overall - but yes, the faster start is a big improvement for me.

[alhbln]

...

I bought two coils to test for my Ignitor install – the Pertronix 40511, 3.0 Ohm that the manufacturer recommends (bypass the stock resistor) and the 40011, 1.5 Ohm for use with the resistor.

...

Overall, the 3.0 coil seemed to work at least as well as the 1.5 Ohm coil w/resistor, perhaps a little better – maybe the tech folks at Pertronix knew what they were talking about.

Your tests prove the theory There should be no difference between the 3.0Ω coil and the 1.5Ω coil + 1.5Ω resistor, as in both setups you limit the maximum current to 4 ampere (A=12V/3Ω). So, if both coils have the same winding ratio, they will create the same spark voltage and spark energy.

[Mikez73]

Mikez73,

I considered the 280zx dizzy route, but from a cost (initial and component replacement) I decided to go this route. The remanufactured dizzy was $55 from Autozone, the Pertronix Ignitor was $69 - so I had a "new" dizzy for $124 that I could convert back to points if needed. Some folks still have some luck using a salvage yard 280zx dizzy, but I didn't want to replace a 38 year old electrical/mechanical part with a 29 year old one.

The car is performing better overall - but yes, the faster start is a big improvement for me.

Can't fault that logic. I wouldn't want to chance a used dizzy either unless it was a gift. I was in the middle of weighing the options myself when I got an email from Rockauto.com that they had a 280zx dizzy on closeout at a price too low to pass up. I completely missed the fact that it was coming with an integrated module. So if I use the HEI I'll have to fab a blockoff plate and the job will be just a little more complicated. But I'm happy with the deal. My only regret was not being able to find a good deal on Magnecor wires. I tried a set of Accel 8.8's leftover from my z31 but obviously they weren't long enough. You can tell I'm a big fan of overkill

I'm sure my $20 NGK wires will be fine.

Anyway great post and I'm sure it's going to help some people.

[motorman7]

4. Install the Ignitor just like a set of points – you may have to rotate the adjusting screw on the breaker plate so that the two attaching screw holes align.

5. Route the wires out through the dizzy body cut-out and make sure that it they will not contact the rotor or shaft. Press in the rubber grommet so it fits snugly.

6. Align the black cylinder over the shaft cam and carefully press down on the shaft – if you aligned in properly you will hear/feel it seat. Once in place it should almost be touching the ignitor. If it is touching, something is wrong with the install, or the dizzy is worn excessively.

A couple observations from my install:

In step 4; it seems very odd to me that they have an adjusting screw and then two fixed countersunk holes. What's the point in the adjusting screw if the assembly is fixed? The second countersunk hole (without screw in the picture), should be a slot just like a set of points. That way, when you assemble the magnet collar and it contacts the 'Hall effects sensors assembly', you can adjust it to avoid contact. Not only do you have worn dizzies, but you have tolerances of manufactured parts (petronics rivet assembly) that vary from assembly to assembly.

After tearing up the green tape on my Petronixs because the fit was too snug, I slotted the countersunk hole. Much better fit...no problems.

In step 5. What's up with the wire routing? The Petronics part should have been designed with the wires coming out the other side so you dont have 3 inches of wire flopping around inside your distributor. It should be on the other end, 1" then out the dizzy, no excess wire issues. The excess wire also tends to get pinched when you put the cap on.

Anyway, just my two cents. Such is the curse of being a Mechanical Engineer. I think they could have done a much better job.

Peace Out

[akorna]

Motorman7,

The cam adjustment screw is just for setting the points. Pertronix could have made the hole larger so you didn't have to touch it at all. My green tape was very close to the Ignitor, probably 0.015-0.018 - and you're right, slotting the lower fixed hole would be the solution - might be another source of unsucessfull installations. Did you get your ignitor replaced, or are you running w/out the tape?

Ditto your observation on the wiring orientation - scratched my head on that one too

I'm an engineer also - I feel your pain.

[motorman7]

Did you get your ignitor replaced, or are you running w/out the tape?

The tape is just kind of worn/slightly torn from contact with the block, so I am leaving it 'As Is' for now. If it gets too bad, I will just re-tape it. I think the tape is just a secondary restraint for the magnets.

Edited March 22, 2010 by Arne
Cleanup of quotes for easier reading

[Zforce]

Did you get your ignitor replaced, or are you running w/out the tape?

The tape is just kind of worn/slightly torn from contact with the block, so I am leaving it 'As Is' for now. If it gets too bad, I will just re-tape it. I think the tape is just a secondary restraint for the magnets.

I glued the trigger magnets in place with zap a gap CA glue, better than that cheap tape. But don't just take the magnets out,if you get the poles wrong the engine will miss. I carefully peeled back the tape and put a dab of white nail polish on each magnet and let it dry before removing the magnets to ensure they go back in correctly. Use the thick gap filling kind available at your local hobby shop.

PS that tape is all that holds those magnets in place.

Edited March 22, 2010 by Arne
Cleanup of quotes for easier reading

[akorna]

Fascinating - no wonder folks go to the 280ZX distributor upgrade.

[alhbln]

Failure of the green tape is one of the two main sources of defects you can have with the Pertronix setup (the other one is a defect of the power transistor, i just managed to kill one while just checking a distributor on the distributor tester, bizarre).

The adjustment screw is for setting the phase correctly (triggering of the magnetic sensor in relation to the position of the distributor axle/cam position), but Pertronix never documented this.