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MG MGB Technical - Pertronix Ignitor Ignition

Hello,

Can anyone share some information for me on the pertronix Ignitor Electronic Ignition systems? It is the system that replaces your points.

Does anyone have this system? Comments good or bad? Is it worth the cost? What will I gain - or lose?

Thanks,

Robert
1973 MGB
Robert Browning

Hi Robert,
I have had the Ignitor Pertronix (sold as Aldon Ignitor in the UK) fitted to my MGB for fours years without problem. The unit replaces the standard points set-up without any alteration, so the distributor can be easily reversed to point should you want/need to.

I have found the car to run more smoothly, the engine starts first turn of the key - reducing drain on the battery, and tuning is noticably easier.

What will you loose? The joy(!) of changing and adjusting points and the initial cost of the system.

IMHO fit it, it's well worth it and Pertronix have an excellent reliability record.

Oh also I changed the coil last year from the standard non-ballasted type on my 72 car for a gold Lucas Sports coil - save your money on that one, it has made no noticeable difference to my car.

HTH
James BGT

I had a Petronix for about 12 years in another type of car and it worked perfectly but be careful with the internal wires so that the rotor doesn't cut them. Don't ask how I know.
Mike MaGee

Hi Robert,

I have used the Pertronix Ignitor sinced back in 1990. This is a very good ignition system. If installed correctly and works the first time, it will work a long time and no need to ever worry about points.

If you have a 45D distributor on your car you would need a LU-143 Ignitor.

Only takes about 5 minutes to install if that. Very easy with instructions. Make sure you install the ground wire. Use the ground connected with your points.

You will be very happpy. It is worth more than the money. You will gain everything, and lose setting and checking your points.

Ray

Ray 1977mgb

I agree, even thought I have the Crane system. Either one is easier to maintain than points. Like Mike said, be careful of the wire routing inside the distributor. Its easy to forget how much the points plate moves, so you need to have enough wire to allow that, without having the wire wear on the rotor. I found out the hard way too (many moons ago.)
Jeff Schlemmer

I fitted the Pertronix system this past fall to my '65 B and while I've had no noticable difference in performance, I'll never have to set or adjust points again. I've also added it to my TF-1500. Plan to fit my '59 MGA soon as well.

Hope this helps - Dennis
Dennis Rainey

If you need to order a Pertronix, call pertronix and get the prper number, order it from Northern Auto Parts. You can get their number online. Northernwutoparts.com, I think. I do not have the number or web site with me. I get mine from them, delivered to my door for less than $70.
Good luck.
steve

I have a couple of things to say about this:

- Moss is more expensive than other sources. Shop around
- There is an Ignitor II and a regular one. The Regular one is the only one available for the B. the difference is that If the key is "On" and the motor is not running, and the angle on the rotor is just right, it will change and burn a capacitor in the unit.
- You will need to rewire the tack directly in series with the unit - easy and better anyway.

I like the unit - much better than points. It runs smoother, much longer and over the whole rpm range. Good upgrade
Frank Baker

Couple of questions -

I was just looking at the archives and some people were saying that they had to move the distributor after installation to get the car to start. Have many people experienced this problem?

Frank, why do I need to rewire the tach? I was under the impression that the tach ran off of the coil in a 73 MGB and not the distributor?

Have many people experienced tach problems after installing a Pertronix unit?

Thanks,

Robert


Robert Browning

Robert,

No problems with Tach. The Red wire from the Pertronix goes to the positve side of the coil. The Black wire to the negative side of the coil. The tach white/black wire stays on the negative side of the coil.

Before you take out the distributor put the car in 3rd gear. Take off the distributor cap. Push the car backwards until the rotor facing the number 1 plug and also your timing mark should be exactly on TDC.

Get a fine marker and put a mark on the distributor body and the clamp. When you install the distributor your timing should be exactly as it was. Easy.

Why Frank mentioned to rewire the tach is a question I have no answer to. You are correct, it stays wired to the coil.

Robert this is a very simple installation. Don't worry, you can do it with the instructions that come with it. Once completed you will be very happy with the outcome.

Ray
Ray 1977mgb

Ray,

Do I have to remove the distributor to install the Pertronix unit?

Also, where is the timing mark you are referring to?

Thanks for your "experienced" help.

You can email at: rlbipi@aol.com

Robert
Robert Browning

Robert,

Sent you a e-mail. Please check.

Ray
Ray 1977mgb

Robert:
If you decide on Pertronix, have a look at the Retro Rockets site. I ordered from them for my v8 conversion. The prices were very competitive, fast service and included free shipping.
Pil

http://www.vintageperformance.com/retrorockets/index.htm
Phil O

James: Just had this system installed in my 79 MGB, no complaints. The idea of turning the key to the start position and having the engine start immediately is a comforting feeling. The points gap would collapse in my former system thus creating a bucking and a backfire through the carburetor scenario. This solved all the problems. If you have a 45D distributor the item is the LU-143 and frot the 25D it is the LU-144

Good Luck

cheers

Gary :>{D
gnhansen

Installed one in my '74 about 6 years ago with the dizzy in place.

As that infomercial says - set it and forget it!
Phil Collura

Absolutey!
And yes, I too know about wires too close to the rotor.
However, I called Pertronix, told them my problem, and sent the [defective]unit in.
They were very helplful, and informed me the unit has a 30 month warranty. And sent me a new unit.
Can't beat that!
And they do make my 'B' run smoother, start faster, etc.
Grass Roots Motorsports magazine did a dynomometer test witha late model 'B' and reported a 2-3 HP increase with it.
Spark is just more consistent, than points/condenser.
Safety fast
Dwight
dwight

The Tack

The tack wired in the original way is (and alway was) weak. I had my tack rebuilt by Nosinger and picked up the wiring through them. A direct in series wiring increases the signal strength and gives one a better, more accurate reading. If you look in the archieves you will see many complaints about tacks and Pentronix. I think this has to do with the Electrolytic capacitors aging. My type of wiring is very direct and very simple. It solves those issues.

The timing does change, but I think (remember) some ablity to "roll" the module to get the gap right. I think if the module angle and the orginal angel of the points differ, you can make it right in the distributor adjustment. One way is to advance it until you get preignition on a hill and then back it off until that goes away. I think if you check that type of adjustment against a timing light, you may get a slightly more aggressive adjustment by hearing the preignition and adjusting back by ear.

This conversion is easy, and it is better. I don't mean to cloud that point. My comments are from the school of hard knocks, if others have had better luck or worked with better cars, great. I do feel like I have experienced the full range of issues in the ignition system.

See ya

Frank
Frank Baker

Frank,

Would you or could you please elaborate on the way you wired your tach?? I have a '65 B and the tach has never been right, reads much higher than actual. I've learned to live with it. I fitted a pertronix this past fall but there was no noticable difference in the tach performance.

Thanks - Dennis
Dennis Rainey

The timing will probably change when switching to Pertronix due to a change in dwell, unless of course your dwell was right on the money to begin with. Changing to an electronic ignition you will never have to dwell on dwell :)
Mike MaGee

Expect the timing to change - so be sure to have
a timing light at the ready.

This happened to me when I installed mine
4 years ago. Haven't had a problem with it since (knock on wood).
Daniel Wong

The Retrorocket site is good . Just get the right Ignitor for your dizzy and be sure to read the notes if yours is a LU-143.
Michael
Michael Beswick

A note of caution concerning the Coil II -

If you install the Coil II with your PertronixII, be sure you pack a standard coil along with your emergency replacement points/condensor set.

The Coil II is a low resistance coil recommended for use only with a current limiting ignitor such as the PertronixII - Use of the Coil II with standard points will result in high current through the points and will melt them down & possibly create a fire hazard.

...Pete
Pete Dickerson

I will email you the drawing (Dennis Rainey, Sacramento, CA-USA, raineys@frontiernet.net ) If any body else wants it, just let me know.

See ya

Frank
Frank Baker

Frank,

Please e-mail me the drawings, too. I have a 18GB engine in my MGA. My V8 is a '67 so I used the VDO 4" Tach and Speedo which fit after a little work with a dremel tool.

Thanks,

Al
Al Wulf

Frank,

Please send me the drawings.

Thanks,

Robert
rlbipi@aol.com
1973 MGB
Robert Browning

The '67 and earlier tachs have an inductive loop outside the tach which drives the tach. Changing the timing duration and/or the clean spark cut off with the electronic ignition makes the tach useless.
The vdo 4" tach fits easily and works great.
Barry
Barry Parkinson

Daniel, or any budy, how do you time an 18V with a euro spec (in this case an Aldon BR101) distributor. My shop set it per 'spec'. static I think, but it pings going up hill and sometims when warm. Thanks
Steve
Steve Meline

Frank,

As I'm gradually getting up the nerve to go with the electronic ignition conversion, I too would appreciate a copy of your drawing. Many thanks,

Joe
lucasj@ms.umanitoba.ca
Joe Lucas

Frank- Hate to play the gimme guy, but my tack has been whack in the 71 for years now. Replaced the voltage stabilizer hoping, but it still flips around. I have the Pertronix, but it did the same with points/condenser, so if you don't mind, I'd appreciate the schematic. And thankyou in advance. Vic
vem myers

I have the crane unit on my 73BGT. I've been very pleased with it except for one thing. In the past year I've cracked two ditributor caps. I put the 40,000 volt coil in as well. Talking to a guy yesterday, he mentioned that with the hotter coils and the electronic ignition, the standard distributor caps (not built to handle that voltage) stress more quickly. Is this true? Has anyone found a better replacement cap?

Thanks,
Dennis

PS. Frank, I would sure appreciate a copy of that schematic as well. Cheers!
Dennis Hosier

James and Dennis,

Hotter coil=more voltage='fatter' spark=allows for wider plug gap.

An uprated coil will make no difference to a well maintained stock ignition setup. It will only come into its own when plug gap, ignition timing and carburettion are also altered to make use of the increased spark available.

No idea about an uprated cap though, sorry ;)
Curtis Walker

Curtis. My experience is similar. The "uprated" coil offers a potential for greater voltage, but does not supply it unless there is a requirement. At idle, both the factory coil and the Sports Coil show about 11K volts. Whether the Sports Coil, when under load, will ever deliver the promised 40K volts, under normal driving with a properly maintained system is not something I can check with the equipment I have available.

I am not sure how any aftermarket system could increase the output of the coil by itself. The coil builds up a magnetic field while the points are closed or the chopper is breaking the beam of light. When the points open, or the beam of light is allowed to pass through a slit in the chopper, the magnetic field in the coil collapses. At that point, a current is induced in the secondary, step up, windings of the coil and continues to build until it shorts to ground throught the spark plug.

When everything goes right, as it should if the high tension (HT) circuit is in good condition, you should be seeing voltages of 20K or less under most driving conditions.

But, if the plug gaps are excessive (I use .035" on all models with sucess), the plugs are fouled, the spark plug wires or the coil lead are deteriorating, the connections at the coil, distributor cap and plugs are not tight and firmly inserted or if the arm of the rotor is a little short, the firing voltages must be higher to cause the spark plugs to fire.

One of the indications of these problems is more rapid wear of the weakest part in the system. Sometimes this is the rotor (some of the Lucas items were too thin and allow the spark to ground through the rotor to the distributor shaft), sometimes the wires and sometimes the distributor cap.

I have been using the NGK plugs (BP6ES) with Robert Bosch wires for several years now and they seem to work well. You have to make sure the wires are firmly, and fully, seated into the coil and distributor cap or they will spark and cause damage to one or both components. In Phoenix, BAP has a good supply of rotors and distributor caps, made in Italy. They seem to work as well as the factory Lucas products, perhaps a little better. But, the entire HT system needs to be checked out and should be in excellent working condition to take advantage of any "high performance" coil or ignition system.

Les
Les Bengtson

Curtis and Les,

Thank you very much for your insight. I was focusing on the failed component when I should have been looking at the entire system. Further investigation on my part is in order.

Thanks again,
Dennis
Dennis Hosier

OK, I sent it the drawings to 5 people 1) Wulfmgbv8@comcast.net; 2) rlbipi@aol.com; 3) lucasj@ms.umanitoba.ca; 4) vemarooski@aol.com; 5). dennis@hosier3.com

If you did not get it then I think I messed up the email address. Please send me an email and I will bounce it back to you

How do you contact the web master? Maybe there is a way to post these??
Frank Baker

Got it. Thanks

Robert
Robert Browning

My wiring drawings are now on the web site at
http://www.mgcars.org.uk/pdf/mgb-pentronix-tach-wiring.pdf
Frank Baker

I just picked up my Pertronix system. In the kit there is a small plastic stip that I assume is to be used a feeler gauge. However, the instructions say nothing about any adjustment. It just says to screw it in place.

Is this plastic strip suppose to be a feeler gauge?

Thanks,
Robert
Robert Browning

Robert,
Enough people have already answered this. JUST DO IT! I have one in my '79 B, '58 A, both '52 T's and my ZBV. Never a hint of trouble.

Roy
Roy Dougherty

I think that is the gap between the pickup (wth the two wires coming out of it) and the rotor shaft
Frank Baker

With the Crane 700 ignition and using a 45,000 v rated coil with a ballast resistor, I find that running a .050" spark plug gap makes the engine run better when it's cold. I think the 700 is a little heavier duty than the pertronix. The Crane 3000 model can run a hi power coil without the ballast resistor. The engine ran fine with the stock plug gap, and I don't have any way of comparing performance before and after, other than the noticeable difference from a cold start up. I use hardly any choke immediately after start up. Much less than before I regapped the plugs.
Barry
Barry Parkinson

I run the XR3000 and bought a spark tester to measure spark strength for comparison reasons. The stock setup with a Sport coil produced about 35K volts, while the XR3000 with the Crane PS91 coil exceded the limits of the tester at 50K. I run a .045 gap and couldn't foul a plug if I tried. I don't know if there is any performance to be gained since I am still running relatively stock carbs with limited air intake.
The XR300 does have a computer variable dwell, increasing as rpms increase. This does ease start-up and increase performance, as well as smooth the idle.
Jeff Schlemmer

Ok, Please see my new thread called, "Pertronix Ignitor Ignition Problem & fuel pump"

Thanks,

Robert
Robert Browning

Frank- Just a final kudo for the schematic. Looks promising. Anything I could do on your behalf? Vic
vem myers

Not a Pertronix, but I can certainly recommend the Lumenition Magnetron electronic ignition - cheap, 5 minutes to fit is brilliant - quick start and faultless running. Only a slight timing adjustment required (was able to start immediately after fitting)
C Dow

This thread was discussed between 22/08/2005 and 08/09/2005

MG MGB Technical index

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