Electronic ignition - revisited

[SorenDK]

Hi guys - this might be a trivial question. I have searched the forum for answers but have'nt quite forund the right one - hoping for help.

The thing is, that i want to install an electronic ignition in my '74 CIS injected 2,7 liter engine. The car is fitted with a Permatune (3 pin) and wired to support a standard point/breaker setup.

Before I hook up the ignition I just want to dobbelcheck the wiring: From the new ignition in the distributor I have 2 wires - black and red. These are "normally" connected to the +/- side of the coil - but since I have a Permatune this is not the case here. I need to connect these differently, right?

In the point/breaker setup I have a white wire running from the permatune to points in the distributor - do I connect this with the black wire on the electronic ignition setup? - and would that be pin C?
Regarding the red wire to pin B? - is that correct or do I connect differenty?

I have troubles identifying pin A, B and C on the permatune... can someone guide me, since none is marked on the permatune.

Thank you so much - you guys rule :-)

Søren

[SorenDK]

This is my guess... correct??

[T77911S]

if you want to improve or increase reliability put in something that replaces the permadoom.
go back to the original bosch or put in an MSD.

the other thing is the permadoom/bosch uses a ground to trigger the CD unit. I don't think what you are putting in will work with the permatune..

you can change to an MSD. the MSD can use either a ground switch to trigger the unit or some thing like what you are trying to put in.

personally I would stay with points and an MSD. its more reliable. but that's me.

[zedsn]

I am running MSD, pertronix and blaster coil in my 2.7 77s and the car starts and runs well.

[SorenDK]

OK - good inputs. I didnt realize the permatune was in such bad standing...:-) Is there really no workaround - it appears pertronix have connected it to a CD... A Bosch unit a assume from the older models. This diagram does not work with permatune? - what about lettering on the permatune unit?... So many questions...:-)
/S

[Jonny H]

Ran a 2.7 a couple of weeks back on our CDI+. Noticeable improvement in pickup, torque and HP.



Dyno report here:

Products

Personally, we don't recommend Pertronix. The quality control on the pickup placement seems a bit poor. Often, they are not evenly spaced around the cam, which gives an uneven signal.

Powerspark seem to be a better alternative.

[mskala]

Originally Posted by Jonny H

... Personally, we don't recommend Pertronix. The quality control on the pickup placement seems a bit poor. Often, they are not evenly spaced around the cam, which gives an uneven signal. ...

Interesting you mention that. That was the reason I switched to optical vane type, it
seems easier to make with precision.

[Jonny H]

Originally Posted by mskala

Interesting you mention that. That was the reason I switched to optical vane type, it
seems easier to make with precision.

Yes, it seems the placement of the magnets in the sleeve is not entirely accurate.

This showed up on our diag software as a cyclic RPM wobble, typically +/- 100 RPM.

Opto sensor makes sense but needs to be kept clean.