Pertronix Issues

[born2cruze]

I recently installed a pertronix ignitor in my 1977 911S
Now it will not start and misfires.
The black wire from the ignitor is connected to the CDI box (green wire)
The red wire is connected to a 12V supply (bottom of engine fuse panel)
Wanted to upgrade my system.
Any ideas or should I just go back to points?

[wayne robson]

Its been 20- 25 years now, but i have used Pertronix starting way back, in american cars,
it depends on what, i will call its model, the early ones,no magnetic ring where very prone to
burning out,one way to do that is if messing around with ingnition on for more than 3-4 minutes, that will burn it out,also if you connect red wire to wrong position ,will do the same. Nowdays Pertronix has fixed this problem with a newer models , called Pertronix 111, this eliminates most of those early problems. Then around mid nineties they had
a magnetic ring which where alot better and did not burn out .But was critical on adjusting the gap between the magneting field,especially if you had a worn distributor
that had more than 15-20 thou wear up and down.
It is a very good product,as long as it is fitted correctly and use there best examples,
but a set of points in trunk is handy.

[Quickstep192]

Here's a post from a person who did an awesome Pertronix installation. It includes a wiring diagram.

Pertronix Installation in '73 911E -- complete with photos

Did you re-time it after installing the Pertronxi?

I have a Pertronix in my car and while doing reasearch on how to install it, I also read that there's relatively little benefit in a car with CDI because the points are really a trigger and not handling voltage from the coil and are therefore less prone to wear.
That said, I didn't remove my Pertronix and they seem to be working fine.

[timmy2]

Please show the wiring to your CDI, should be white wires if original for a '77.

[born2cruze]

Thank you for your replies,

Quickstep192, I attempted to re-time the Porsche after installation, (TDC set at #1 spark plug) although it failed to start and backfired.
What did you connect your red and black to, during your installation.
I'm beginning to think that connecting the red wire to the bottom of the rear fuse box may be wrong even though it is activated by the switch and is 12V.

timmy2, enclosed is a picture of my CDI box, three prong and ground
A-white to coil
B-red to switch, battery
C-green to distributor
This is the hookup when I purchased the car.

Anymore information would be appreciated.

[Walter_Middie]

http://www.pertronix.com/tech_suppo..._CD_diagram.pdf

1. The red wire from the CDI (B) connects to the Ignitor Red wire. This is +12V from the ignition switch.

2. The CDI (A) connection goes to the positive side of the coil. This was the same wire originally connected to the positive side of the coil.

3. The Pertronix black wire connects to the negative side of the coil, and to a ground wire.

Also make sure the magnet is going all the way down on the distributor. Measure how the rotor fits without the magnet on the distributor, then measure the rotor with the magnet on there. If the magnet is not seating all the way, you'll have to take a small file and remove a small amount of material from the six flats inside the magnet. It doesn't take much material removal - so go easy.

[Quickstep192]

I connected my red wire to the middle fuse because the bottom position was occupied. I think as long as it's switched +12v you're good. If it's on all the time, I think you can fry the contacts. Also, disconnect your tach until you get everything squared away. I fried mine during my trial and error wiring adding considerable expense to my project.

[born2cruze]

Thank you again for your response.

Walter_Middie, Unfortunately couldn't open the pdf file, good idea regarding the proper seating of the magnet, it did take some doing to get it to seat properly and there is a slight gap between it and the rotor, where would the green wire from the CDI box that originally went to the distributor be connected?

Quickstep192, good idea regarding the tach, where did you connect the green wire from the CDI box?

[Quickstep192]

I connected the Black wire from the Pertronix to terminal "C" on the CDI box. I followed the attached wiring diagram.
Do keep in mind that mine is a '73, so things could be different on your '77

[Walter_Middie]

where would the green wire from the CDI box that originally went to the distributor be connected?

I thought the green wire was something a 3.0L had. Do you still have the original engine from 1977?

[gomezoneill]

Put the points back in.

[Jonny H]

Originally Posted by gomezoneill

Put the points back in.

+1.

I've scoped the output of several Pertronix modules and found the magnets aren't always set at even spacings in the plastic ring. This means the timing is all over the place for each cylinder.

That's a huge fail. What are these companies thinking?

[supdaf]

I bought an ignotor II, I think, a few years back for my 76. I had the engine out doing transmission work at the time so the install I believe was sufficiently elegant. Number one rule, "thou shalt not cut the factory harness."

timing was at the other end of the "slot." no big deal I thought. Engine had a hard time coming back to idle. would hang up at 2K-1.5K and then slowly come down to proper idle. I assumed vacuum leak and spent many hours chasing such.

I also had a high end miss at about 6K...in three gears, exactly at the same rpm. I was already illegal everywhere so I did not try 4th and 5th. I drove home re-installed the points and all my issues went away.

As you might expect I am kinda sour on pertronix. For me 100 bucks wasted.

[Walter_Middie]

I have had Pertronix for many years in my car. No issues ever. Runs great. I would recommend Pertronix without hesitation.

[Quickstep192]

Born2cruze,

Did you get this sorted?

[born2cruze]

Sorry guys, had to leave for the weekend.
I haven't sorted it out yet, but I did hook it up like Quickstep192 diagram pointed out. (I had the same diagram)
Walter_Middie, The engine is original to the car 2.7
I think that Jonny H is on to something as it seems that the timing is all over the place.
I have contacted Pertronix to see what they have to say, haven't heard back yet.
To bad Pertronix really has worked well in my mach1 for years