Pertronix Electronic ignition

[shaunroche]

Hello everyone, I've just ordered a Pertronix ignitor2 and before it arrives, I'm intrigued as what to do with the pink and white ballast resistor wire in the car's loom: do I cut it off making it as short as possible or just detach it from the white/yellow wire?

I assume this is it here is it?

[soe8m]

I think you have two white/yellows there and one pink/white. If so, you can cut the pink/white. You will have the other end of the white/yellow on coil positive and a new white wire from the fusebox to the ballast resistor.

Jeroen

[shaunroche]

I think you have two white/yellows there and one pink/white. If so, you can cut the pink/white. You will have the other end of the white/yellow on coil positive and a new white wire from the fusebox to the ballast resistor.

Jeroen

Hi Jeroen, are you saying cut the pink wire and then add a new wire from the white wire going into the fuse box and fix it to the pink wire?

The Ignitor2 that has arrived has a 0,6 ohm coil: the engine is running as though it is now on 3 cylinders, but I haven't timed it up yet. Pertronix say that the coil shouldn't require the ballast resistor wire detaching, just leave it as it is....not sure now!

[GrahamFountain]

Does this unit take separate power, and do they tell you not to take that from the ignition side of the coil primary when there's a ballast resistor in the circuit?

I know some of the diagrams for the electronic ignition units for the 45D4 just show power taken off the top of the primary coil. If you do that, I'm told they can work well enough to start, but don't exactly run very well.

Instead, with the ballast resistor in circuit, you need to power those units separately, e.g. off the ignition switch (white wire) side of the fuse. You can take power off the fused side, but when that fuse blows, it will really suck.

Also, if you do take out the resistor by cutting/disconnecting the pink and white wire, then the white and yellow wire that connects to the starter solenoid isn't needed anymore. It won't hurt to leave it in: it just isn't doing any good, as the top of the coil will already be at 12V whenever that would supply 12V; because you will have connected the top of the coil to the ignition switch side of the fuse.

I assume you have the circuit diagram, but the first attachment is a copy of the top part in case. I assume it's this diagram, not the earlier one, since there's a mention of two white and yellow wires connected to the pink and white (KW) ballast resistor wire. You should be able to see the connections to the primary coil (9) from the solenoid on the starter (7), and the connections to the ballast resistor (8) which is powered from the white wire side of the fuse (31).
The second attachment is what you should have for a 12V coil fitted. I haven't included the wiring for the electronic ignition unit, of course. Apologies if this is all redundant.

Graham

[dursley92]

Petronix fitting instructions, fitted mine last month.

[GrahamFountain]

Clearer than the instructions for the 45D electronic ignition unit from Alibaba, then. But what could you expect for a tenner?

Graham

[soe8m]

Do you use a ballasted coil and seperate resistor?

Jeroen

[shaunroche]

Thanks for the replies everyone, very much appreciated.

After eventually speaking with Pertronix, it seems I can ignore the ballast resistor wire and just put the red dizzy wire to +ve and the black to -ve on the coil and all seems fine.

The misfire at high loading is still there though and after I changed the alternator ( the ignition light wasn't illuminating and I could see it was under charging), it cured it.....for a while, then it came back, with the ignition lights coming on on the dash board and the ampmeter showing over charging (whilst driving) with a big missfire at the end of 3rd gear and in 4th at high loading ....so no change.

So far I've changed from points to Pertronix, new dizzy cap and leads, both Ambassador type and standard, the plugs and the alternator, all to no avail.

On tick over the rev counter has started going round to max and then zero before returning to idle....it's driving me mad.

[soe8m]

So, what coil, what cap, what rotorarm, what leads and what plugs? Mistfire at high revs is most of the time a too weak spark or the spark elsewhere.

Jeroen

[shaunroche]

Ignitor2 coil and Pertronix magnetic ignition, powerspark 8mm leads, new ambassador cap, powerspark red rotor arm, NGK plugs.

Also used standard Sprint cap and leads with NOS black short rotor arm.

The only constant I suppose is the type of plugs used.

[GrahamFountain]

So far I've changed from points to Pertronix, new dizzy cap and leads, both Ambassador type and standard, the plugs and the alternator, all to no avail.

On tick over the rev counter has started going round to max and then zero before returning to idle....it's driving me mad.

Do you have anyone near with a rolling road? With the car hooked up to their ECG, they should be able to see where the misfire is coming from, on load at revs. You'll also get a power measure as well. The last time I asked a price for a diagnostic run near me, Warton, it was, IIRC, £70. But, it's much cheaper than a psychiatrist - no comfy couch or certificate to say you're now sane, tho.

Tacho: have you checked the connections to the meter? I had something v. similar two days ago, and it was a lead falling off a spade on the back. Pushed it back on and all fine now.

Graham

[soe8m]

Ignitor2 coil and Pertronix magnetic ignition, powerspark 8mm leads, new ambassador cap, powerspark red rotor arm, NGK plugs.

Also used standard Sprint cap and leads with NOS black short rotor arm.

The only constant I suppose is the type of plugs used.

Not alway's the one constant is the cause. Replacing all can have same symptoms caused by different parts/reasons.

Is your baseplate earthed? There should be a little wire in the dizzy from the moving top part to one of the screws that hold the baseplate

Is the 'Ignitior 2' coil a flamethrower 2 type? These aren't all ideal to be used on the type Pertronix you have. The Ignitior 2 can handle 0,6 Ohm coils and make sure this or the 1,5 Ohm one is the one you have for maximum spark available. Note: a coil gives as much voltage needed for the plug to spark. So a super high power coil IS CAPABLE of these high voltages but these voltages are never needed. A Lucas dizzy cap would scream for help when 45.000 volts are going through the contacts and your red rotor would instantly turn into black.

Can you measure the resistance of your HT leads? The powerspark leads are the carbon type and do have resistance. It's twice as the plug lead and the kinglead is the total HT resistance so measure both and add.

5 Kohm in leads or caps is what you want in total in your HT to have a stable spark. Some plugleads can have 20 Kohm and then add a 10 - 15 Kohm kinglead..

Resistor leads do demand more of a coil. There's the 'airgap/mixture' resistance to overcome to have a spark. The voltage needed for that is generated and delivered by the coil. More resistance in the HT does mean the 'airgap/mixture' resistance AND the HT lead resistance to overcome. A slightly smalller spark because of less engery but a higher voltage needed to overcome the total resistance to spark at the plug. Inferior coils can fail not being able to deliver such a voltage, causing a misfire. Your high power coil can deliver the higher voltage but this higher voltage goes also through the rotorarm and the cap and these are absolutely no high super power, probably Chinese repro. The red rotorarm is one of the better to buy. That means better than the current black Chinese Lucas ones but still way off the quality of a NOS Lucas rotorarm. The red ones are the best recent fabricated to buy but that doesn't mean that these are also very good.. Some are shiny red and some are matt red so now manufacturers know people buy only red rotorarms they change the colour..

You can check the airgap of your NGK's or replace these to be sure.

The thing is you have a very good ignition setup but the repro Lucas parts are the weakest link. Try to source a genuine NOS cap and rotorarm to be sure these are of a somewhat quality. Fit HT leads of around 5 Kohm. That is also the original setup. The leads are copper core and the green kinglead is the 5 Kohm restance factory fitted at Sprints and 1850. Before getting to theoretical, 5 Kohm IS NEEDED for a decent spark. All coppercore isn't good either. Some plugs have resistance. When you have a NGK plug with an R in the code the plug resistance will be sufficient.

5 Kohm in total doesn't add much extra voltage and will have less strain on the cap and rotorarm. Denso irridium plugs are constructed that these need a lower voltage to spark. So less voltage demanding from the coil/going through the cap and rotorarm.

Good luck.

Jeroen

[shaunroche]

Hi Jeroen, than you for your continued support, it is very much appreciated!

The rotor arm and dizzy cap that are being used are off an old original good condition engine so they are not reproduction. In addition to them, I have used the newer red rotor arm with reproduction ambassador cap and the powerspark leads and I am still getting the misfire.

Yes the base plate is earthed.

The next thing to do is fit some new magnecor leads and check the plug gaps - what gap do you recommend please?

The issue I had on Sunday at the Lotus test track was the first three runs were un eventful, but the subsequent two a misfire developed and at the end of the long straight could feel the car retarding I think - so it seems to start off ok and then as the say progresses, it gets worse....

Timing - Pertronix advise that the timing should be advanced to 12degrees...I set it at this for the first few runs and then advanced it a bit more - it didn't run any differently I don't think but my top speed was a little quicker at the end of the straight, but then the Ignition light was illuminating and I noticed it was over charging.......

The only thing that has now not been changed is the alternator - the dizzy is new (refurbed by Distributor Dr.), the dizzy caps and leads are Old stock and new, the ignition system and coil is new and the plugs have been changed.

Could it be a fueling issue? Gold top Facet electric pump and Malpassi filter king Fuel Regulator are fitted...

I can't understand why it starts off ok then deteriorates....it was fine all day at Cadwell, started off OK but deteriorated at both Goodwood and Hethel....

[soe8m]

Can it be temp related? When you start all over again from cold after the misfire, does it stay misfiring from then or when cold does it disappear and starts again after a few runs?

How are the plugs? All the same colour?

When it does misfire, does that stay at mid revs and idle also then? If so you can pull at idle one by one the plugleads off to see which cilinder it is and if it's still the same cilinder that misfires. Maybe it's random. A IR tempgun on the exhaust manifold can also show which cilinder is faulty.

If it's temp related and for example a cilinder sucks in coolant then, the plug should show. Also fuel related issues do show at the plugs. It can also be valve play. When a valve just not closes at a very hot engine by wrong play it misfires also. A slightly sticking valve when hot.

When you are sure the ignition parts are all ok there's more to investigate.

Jeroen

[shaunroche]

Hot, off the start line, up to 7k revs in 1st and 2nd, no issue. Continue up to 7k in 3rd and into 4th and the misfire occurs.
So on fast circuits like Goodwood it's a nightmare.

On short circuits or hillclimbs where you may not get in to 4th where it's predominantly in 2nd and 3rd gear, again, no issues.

Could there be a short in the ignition circuit in the harness? Would that cause it?

I've ordered a new fuel pump and alternator and tomorrow will fit them, blow out the fuel line and check the fuel pressure and look at all the jets in the carbs etc.

Thinking about it, it did this once or twice with the previous engine so it's either an ancillary, the fuel or the carbs....