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Why points are better than Pertronix... since u asked

Posted by B-racer 
Terry Ingoldsby
Calgary, Alberta, Canada   can
1971 MG MGB

Quote: 25D or 45D ignitor2 with adaptive dwell. with flamethrower 2 45k volt coil

Okay - before we go any further - are we talking Ignitor I (fixed dwell) or Ignitor II (variable dwell). And what did Moss sell me several years ago? I'm going to have to pull the cover off my distributor and look it up.

The Pertronix catalog is at http://www.pertronix.com/catalogs/pdf/ptx/2012/Pertronix2012.pdf

Jeff - have you compared Ignitor I vs Ignitor II? The variable dwell feature should provide a measurable benefit. Also, voltage is not as important as energy. I agree that the plugs probably fire at less than 10 KV - and once they fire they clamp the voltage. However extra energy can make the spark hotter and better able to ignite the mixture under adverse conditions.

I've got to check if I have the LU142A or the 9LU142A. If it is the former, then I will likely switch to the Ignitor II and keep the Ignitor I in my battery box as a backup.



Terry Ingoldsby
terry.ingoldsby@DCExperts.com
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JoeReed Avatar
Joe Reed
Cordova, Tennessee, USA   usa
1978 MG MGB "Kermit"
1997 Jaguar XJ6 (X300)

Interesting that some people apparently carry spare points with them. Why? Maybe it's just because they're so small it's no problem. I'm 64 years old and I've never once had an issue on the road that required a change of points. Had one condenser fail suddenly, but never a sudden points issue.

I also prefer to yank the distributor out and gap the points on the bench. I find it's quicker and easier to do it accurately that way. Having poor eyesight doesn't help...and it's awkward to be fiddling with holding the feeler gauge, keeping the gap correct and tightening the screw while bent over the wing with the bonnet prop rod partially in the way.

Many, many years ago I had a handy little tool that I wish was made for our distributors. It was just a set of rings sized to fit the common US distributors. To set the points, you'd just open the points....drop the ring over the distributor cam....release the points - and adjust them so that the gap was closed. When you removed the ring, the gap was perfect every time. They came in real handy when setting the points on a car where the distributor was in a bad location (think Chrysler slant-6!). Of course, the best was probably the GM distributors where you could adjust the points from outside the distributor using a dwell meter with the engine running...




79mgbv8 Avatar
Gil Price
Constable NY, USA   usa
1971 MG MGB GT
1976 MG MGB
1979 MG MGB V8 Conversion "Rumble Bee"

Hap X 2

I have had 2 Petronix failures that compelled me to seek a better solution --2 25D dist rebuilt by Jeff with points and no problems since in about 5 years. I tried to install the correct Petronix on my Ford V8 distributor and it would not even start --points lasted only 5-6000 miles so now have a Accel electronic module that lasts about 30 k miles. Petronix said nothing was wrong with the unit I sent back --its on the shelf in my shop... Jeff is the man
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ltelencio Avatar
LARRY TELENCIO
Naples, FLORIDA, USA   usa

Hap X3

Have benn running Jeff's dizzy for five years, still great!

Larrysmileys with beer
riley1489 Avatar
Bruce Hopgood
Great White North, -, Canada   can
1953 Jaguar XK120
1959 Riley 1.5 "King George"
1973 MG MGB

I currently have 2 B series powered LBC that are using distributors that have been refurbished by Jeff, I have no intention of going away from points, the approach is simmple, inexpensive and being a bit of a 'dinosaur' I can mend them on the side of the road if needed, (never been there!). My mind is made up so don't try to confuse me with the facts.

Take a look here, how one chap sorted his B series engine ..............

http://retrorides.proboards.com/index.cgi?board=readersrides&action=print&thread=37297

Bruce
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underdog Avatar
Jim Underwood
Pittsburgh, USA   usa
1972 MG MGB
1980 Triumph TR8 "Fabulous Trashwagon"
1999 Chevrolet Corvette "Darth Vader"
1999 Chevrolet S10 "Spare Change"
2003 Jaguar S-Type "Eleanor"

Did a quick search on Yellowbullet and couldn't find one negative post about Pertronix products. Actually quite a few said their stuff works great and the company is good to deal with. Still most all the racers favor MSD products by a large margin. So I have to wonder if these failures are something unique to the Lukas conversion products or something to do with the cars themselves such as voltage spikes ect.
pinkyponk Avatar
Adrian Page
Berwick, Nova Scotia Canada, Canada   can

In reply to # 2312184 by underdog Did a quick search on Yellowbullet and couldn't find one negative post about Pertronix products. Actually quite a few said their stuff works great and the company is good to deal with. Still most all the racers favor MSD products by a large margin. So I have to wonder if these failures are something unique to the Lukas conversion products or something to do with the cars themselves such as voltage spikes ect.

This is a product that is intended to be installed by the average Joe car owner. I found a number of mentions on the web about owner/mechanics not removing ballast resistors when installing the Pertronix/Accuspark/Powerspark units. Others reported hooking the wires up wrong and frying them. One fellow reported sending his back and it was returned to him because there was nothing wrong with it. Sounds about right. Owner/mechanic error.
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Terry Ingoldsby
Calgary, Alberta, Canada   can
1971 MG MGB

Okay - I went out and pulled the cap off my distributor. The numbers on the Pertronix don't correspond to their catalog numbers (of course not) but it does clearly say "Ignitor" and not "Ignitor II".

So - why is Moss only selling the Ignitor? Or did I just buy before the Ignitor II was available?

Is anyone out there running the Ignitor II (for sure) - were there any observable differences between it and the Ignitor?



Terry Ingoldsby
terry.ingoldsby@DCExperts.com
bobmunch Avatar
Bob Muenchausen
PC, Oregon, USA   usa
1968 MG MGB GT "Traveler"

I put Pertronix right up there with Audiovox cruise controls - meaning they will always be suspect to me given their past histories among various owners, not just my own experiences with them.

I do run the Crane XR-700 in one of Jeff's Distributors. No offense meant to Jeff's opinions or his choice of triggering, but much like Terry, running with the Crane optical trigger has meant no retiming and pretty consistent timing over as many years as I've had Jeff's Dizzy. My personal choice for triggering may not mean that I get the benefits of his points, but use of the optical points substitute has not seemed to have taken much away from his distributor's performance in use on a daily driver like mine. (I personally think that the term, "electronic ignition", is a misnomer and implies much more than what is actually performed by a Crane or Pertronix unit - they are spark triggers and that is just about all)

Anyone who has read the threads on MPG and tuning should know that I get what I consider to be very good performance from Jeff's Dizzy, even without his points, which, frankly, seems far more of a testament to the performance he has built into his dizzy's IN SPITE OF the choice of points or points substitutes used. The functioning of Points or not is but one function of the whole, and when you narrow the performance differences between mechanical and electronic triggering sufficiently, what I would think you are left with, is the rest of the mechanical device controlling those triggering devices - namely the quality of the dizzy itself. JMO



Useful info about those rubber rotary seals on your crank, axles, etc >>> http://www.rlhudson.com/Shaft%20Seal%20Book/index.html

SU Carb info needed???? Go here first! >> http://www.teglerizer.com/sucarbs/index.html

A collection of photos of one of the MGB GT cutaway cars at the BMH Museum at Gaydon can be found here >> http://www.cibolas7.net/resources/cutaway.htm

A PDF copy of The British Leyland Emissions Control Manual Thru 1973 may be found here >>
https://www.dropbox.com/s/dgjgbxszv1h22hy/MG%20EMISSIONS%20MANUAL.pdf Read pages 4-1 thru 4-14 for instructions as to procedure and sequence of work.


Nuffield Australian MGB Assembly Manual >> http://mgbsmadeinaustralia.org/wp-content/uploads/2012/07/mgb_ckd_assy.pdf

And, of course, this old crock >> http://www.britishcarforum.com/bobmuenchausen/4436.html



Edited 1 time(s). Last edit at 03/13/2013 02:27PM by bobmunch.
RAY 67 TOURER Avatar
Ray Marloff
Fort Bragg, CA, USA   usa
1967 MG MGB "My Girl"

I installed a Pertronics unit in a brand new distributor, that I purchased from Moss, when I installed one of their supercharger kits. The distributor was a clone of the 45D. The magnet was a very sloppy fit and the pickup coil was so far out of alignment to the magnet that it caused the rotor to burn a hole through the side of the distributor cap in less than 1,000 miles. I'd never use one of their products again. A bad design, poorly executed. RAY
1977 MGB Supercharged Avatar
Ray Wyberski
Pago Pago, American Samoa   asm
1977 MG MGB "Jazzy's Car"

Here is an article called "ZAP IT" written by Carl Heideman. http://classicmotorsports.net/articles/zap-it/

He compared points, ignitor and ignitor with MSD6A using the same vehicle on the same dyno. (We have dyno tested several MGBs and MGAs that have received the Ignitor upgrade, and it almost always adds 2 to 3 horsepower at the wheels while also improving starting and drivability. Looking at the dyno graph, you can see not only the power increase from the Ignitor, but that the line is smoother, indicating better drivability.)

Dyno graph: Blue Line = Points, Green line = Ignitor, Red line = Ignitor & MSD6A.

Attachments:
igndyno.jpg (75.3 KB) –
igndyno.jpg

herculesmgb1971 Avatar
gerard boulanger
Hercules, CA, USA   usa

Maybe points are better than x, y or z because they need service from time to time while electronic systems do not...
Terry Ingoldsby
Calgary, Alberta, Canada   can
1971 MG MGB

Here is a *great* article on dwell http://www.dtec.net.au/Ignition%20Coil%20Dwell%20Calibration.htm

I am trying to find out more about the Ignitor II for our engines. It has the variable dwell feature.

For those that don't want to read the article (long and technical - but lots of pictures!) here is the synopsis.

1) To get optimal output from the coil it must have time to build up the magnetic field. The time (on simple distributors) is controlled by two parameters: Dwell angle (the fraction of a rotation that the points are closed) and RPM (the higher the RPM the shorter time it takes to rotate through the dwell angle).

2) If the time the coil is building the field is too long, the coil can end up saturating. This generates extra heat in the coil. In the case of transistor controlled systems it may also overheat those components. So, too great of a dwell angle at a low RPM is a problem. The low RPM situation sets the upper limit to the dwell angle. Also, when the engine is running slowly, it makes sense to have a long duration spark. It gives the mixture more time to ignite while the slow moving piston is near TDC.

3) At high RPM the rotation is much faster (and the time for building the field is less). So, the dwell angle that was sufficient at low RPM is no longer long enough to fully charge the coil. Also, a long spark is no longer useful. The piston is moving so fast that, if the mixture doesn't ignite almost instantly continuing the spark doesn't matter much because the piston will already be nearing BDC by the time the spark finishes. Even if the mixture finally ignited, it wouldn't add much power.

4) Ideally, we want a smaller dwell angle at low RPM (which will not overload the coil and will give a nice long spark) and a greater dwell angle at high RPM (where we are more than happy to sacrifice some of the spark duration to get a longer field build-up in the coil).

Fixed dwell systems are basically a compromise. The dwell is not ideal for either low or high RPM. It works at both but is really optimized for mid-RPM.

In practice, a variable dwell system (such as the Ignitor II) should give better starting performance and better high RPM performance. I think that most of the comments critical of the Pertronix are directed toward the Ignitor I (fixed dwell) system. It would be interesting to see scope trace comparisons of Ignitor II vs points (or Ignitor I) at low and high RPM.



Terry Ingoldsby
terry.ingoldsby@DCExperts.com
B-racer Avatar
Jeff Schlemmer
Minnesota, USA   usa

There's a guy who guts condensers and install electrics into them, to act like your thyristor, but the points must be perfectly clean in order to work. Even a finger print on the contacts will malfunction. I've never gotten one to work properly.

I don't have a legitimate reason why the TR6 gained 39 hp. Its insane, but it did happen. It WAS firing on all 6 cylinders, with a slight misfire present as read on the air/fuel meter. It actually read lean, since the fuel was condensing into a solid and solid fuel can't be read on the meter. It smelled (and was) slightly rich. If we leaned it out, it probably would have gained power on the Pertronix, but it had triple Webers, so that would have gotten very expensive. Fixing the ignition was step #1, by simply trying points. That made the power we wanted, so deeper investigation wasn't in the budget. It was fixed as far as we were concerned, and so well that we actually broke the overdrive transmission with all the torque - 157 ft lbs if I recall correctly. That car would easily break loose in 3rd gear when you hit it hard, enough to spin the car at 60 mph. Not for the faint of heart. Certainly well tuned to say the least, and it draws crowds everywhere it goes. As I said, its not a typical response when you change to points, but it DID happen so stop giving me shit about it. Come here and I'll show you the dyno sheets.

I never did recheck the electronics that were in the TR6, but they worked flawlessly on the distributor machine. The fault lied in the secondary voltage when the electronics triggered the coil. The triggering signal wasn't clean, and no we never changed the coil or any wiring. The timing stayed at 14 BTDC at idle the whole time. Had we advanced the timing, over inflated the rear tires, or tried any of numerous tricks, the hp would have gone up farther.

Now as far as wear affecting point signals, yes a loose shaft bushing or worn breaker plate affects points signals. That's where my rebuilds come in. Use a premium bushing that's hand fit to the shaft perfectly, and it will wear well and last long. Mass assembly will give you looser fit, more timing variation, and a shorter life, unless you get very lucky. On the Hotrod testing, when you use an over-the-counter distributor that's not perfect, points don't work as well. The fact that they fared well is a testament to their function. Do the same comparison with one of my distributors and they do even better, and the effect should hold for at least 50k miles, unless you seriously overheat the engine or cause other premature damage to the distributor.

I think I've beat the dead horse long enough... Those who believe do. Those who don't never will. I'll go back to explaining my experiences to customers one by one and keep surprising shop owners when my experiences match theirs... I know I'm not the only person who learned the hard way!



jeff@advanceddistributors.com
Terry Ingoldsby
Calgary, Alberta, Canada   can
1971 MG MGB

Jeff - I'm still waiting to hear if you've ever worked with Ignitor II or just Ignitor I? I really want to know because I'm considering the Ignitor II.



Terry Ingoldsby
terry.ingoldsby@DCExperts.com
Dandare Avatar
Danny H
Sydney, Australia   aus

In reply to # 2311735 by Dandare I'd like to ask Jeff what his opinion/experience is of the Lucas 45DM electronic distributor. I've been running one (45DM6) in an older BMC car, Not an MG, for about six years with no problems so far.

Danny

Just bumping this one...Jeff I'd appreciate your ideas on this system

Danny
pinkyponk Avatar
Adrian Page
Berwick, Nova Scotia Canada, Canada   can

In reply to # 2312785 by B-racer There's a guy who guts condensers and install electrics into them, to act like your thyristor, but the points must be perfectly clean in order to work. Even a finger print on the contacts will malfunction. I've never gotten one to work properly.

I don't have a legitimate reason why the TR6 gained 39 hp. Its insane, but it did happen. It WAS firing on all 6 cylinders, with a slight misfire present as read on the air/fuel meter. It actually read lean, since the fuel was condensing into a solid and solid fuel can't be read on the meter. It smelled (and was) slightly rich. If we leaned it out, it probably would have gained power on the Pertronix, but it had triple Webers, so that would have gotten very expensive. Fixing the ignition was step #1, by simply trying points. That made the power we wanted, so deeper investigation wasn't in the budget. It was fixed as far as we were concerned, and so well that we actually broke the overdrive transmission with all the torque - 157 ft lbs if I recall correctly. That car would easily break loose in 3rd gear when you hit it hard, enough to spin the car at 60 mph. Not for the faint of heart. Certainly well tuned to say the least, and it draws crowds everywhere it goes. As I said, its not a typical response when you change to points, but it DID happen so stop giving me shit about it. Come here and I'll show you the dyno sheets.

I never did recheck the electronics that were in the TR6, but they worked flawlessly on the distributor machine. The fault lied in the secondary voltage when the electronics triggered the coil. The triggering signal wasn't clean, and no we never changed the coil or any wiring. The timing stayed at 14 BTDC at idle the whole time. Had we advanced the timing, over inflated the rear tires, or tried any of numerous tricks, the hp would have gone up farther.

Now as far as wear affecting point signals, yes a loose shaft bushing or worn breaker plate affects points signals. That's where my rebuilds come in. Use a premium bushing that's hand fit to the shaft perfectly, and it will wear well and last long. Mass assembly will give you looser fit, more timing variation, and a shorter life, unless you get very lucky. On the Hotrod testing, when you use an over-the-counter distributor that's not perfect, points don't work as well. The fact that they fared well is a testament to their function. Do the same comparison with one of my distributors and they do even better, and the effect should hold for at least 50k miles, unless you seriously overheat the engine or cause other premature damage to the distributor.

I think I've beat the dead horse long enough... Those who believe do. Those who don't never will. I'll go back to explaining my experiences to customers one by one and keep surprising shop owners when my experiences match theirs... I know I'm not the only person who learned the hard way!

So.... trying another Pertronix may well have had the exact same result as switching to points.

Scientific testing procedures are fairly basic to understand and follow. Change a single thing and note the result. Any huge and un-duplicatable findings are discarded or further investigated to assess what happened.

Your customers seem to be astounded that the knackered distributor they send to you miraculously works better once it has been completely refurbished.

You still haven't given a reason why "points are better", only anecdotal evidence of your personal experiences. Other data presented in this thread (Car Craft and Classic Motorsports) indicate the opposite of your findings. Saying "points give more power" says nothing as to why points give more power. When something cannot be quantified or explained it is subject to doubt.
Dave Braun Avatar
Minnesota, USA   usa
1952 MG TD "Tommy"
1970 MG MGB "Maggie"
1974 Triumph Spitfire 1500 "Sammy"

Adrian,

Some of us aren't in the business of horsepower analysis on one-off engines, as customers won't foot the bill. Once their engine is developing the desired power, they tend to stop paying. I've said it before, Pertronix will mask problems on poorly functioning distributors, and will give improved dyno results on engines so equipped with poor distributors. On distributors with excellent clearances and advanced curves tailored to the cam and carbs, points will out perform Pertronix. I think the Eclectic Motorworks results are based on poor distributors, so their results show a mild improvement with the Pertronix, something that has not been borne out on the engines I've built. But Jeff is just down the road and I try to get the distributor rebuilt on every car I service, to the point of loaning a distributor until the one from Jeff arrives. I do give the option of points or Pertronix, because everyone has different goals.

I get very few requests for rebuilds on carburetors for different needles, which tells me only a small percentage of people looking for help on carbs are improving their horsepower. But my mantra is always the same, get your breathing in order (valves and compression) the fire in shape (ignition, dwell and timing) and finally fuel in order. Doing one or two will not yield the desired results. Honestly? I drive a bone stock MGB engine, with the exception of the oil cooler thermostat and the lack of an air pump. It gives a nice balanced feel on the road which is where I use it. The breathing, fire and fuel is in order. The Spitfire I'm doing right now is getting a cam with a previous profile, Eurospec Carbs and inlet manifold, and Eurospec exhaust. I'm considering distributor options, some of which require an electric tach... Because in 74 the 1500 engine when Federalized was ridiculously down on power. I want what Europe had in 75, which won't exactly set your heart afire.

There had to be something terribly wrong with the phasing and timing of the Pertronix module on the TR6. But when the lost horsepower was found, Jeff's customer stopped looking. Most people want a well running engine with smooth power. I concentrate on those builds. Jeff is a bit more into the gobs of power approach. But they all tend to be one-offs. I bet 95% of the distributors he does are for fairly stock applications, but as I said in a past MGB Driver article what he does with a distributor far exceeds what Lucas or Delco could do building thousands a day.

So can I fully explain the huge jump in horsepower on the TR6? No. But that's where we stopped. There wasn't R&D money for more. I'm not arguing with you, I'm just explaining the back story.

Warmly,
Dave

dbraun99 LLC   – Hastings, Minnesota USA dbraun99 LLC provides complete bench services on SU Carburetors. We also provide advice, repairs and restorations of both systems and complete cars.

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pinkyponk Avatar
Adrian Page
Berwick, Nova Scotia Canada, Canada   can

In reply to # 2313110 by Dave Braun Adrian,

Some of us aren't in the business of horsepower analysis on one-off engines, as customers won't foot the bill. Once their engine is developing the desired power, they tend to stop paying. I've said it before, Pertronix will mask problems on poorly functioning distributors, and will give improved dyno results on engines so equipped with poor distributors. On distributors with excellent clearances and advanced curves tailored to the cam and carbs, points will out perform Pertronix. I think the Eclectic Motorworks results are based on poor distributors, so their results show a mild improvement with the Pertronix, something that has not been borne out on the engines I've built. But Jeff is just down the road and I try to get the distributor rebuilt on every car I service, to the point of loaning a distributor until the one from Jeff arrives. I do give the option of points or Pertronix, because everyone has different goals.

I get very few requests for rebuilds on carburetors for different needles, which tells me only a small percentage of people looking for help on carbs are improving their horsepower. But my mantra is always the same, get your breathing in order (valves and compression) the fire in shape (ignition, dwell and timing) and finally fuel in order. Doing one or two will not yield the desired results. Honestly? I drive a bone stock MGB engine, with the exception of the oil cooler thermostat and the lack of an air pump. It gives a nice balanced feel on the road which is where I use it. The breathing, fire and fuel is in order. The Spitfire I'm doing right now is getting a cam with a previous profile, Eurospec Carbs and inlet manifold, and Eurospec exhaust. I'm considering distributor options, some of which require an electric tach... Because in 74 the 1500 engine when Federalized was ridiculously down on power. I want what Europe had in 75, which won't exactly set your heart afire.

There had to be something terribly wrong with the phasing and timing of the Pertronix module on the TR6. But when the lost horsepower was found, Jeff's customer stopped looking. Most people want a well running engine with smooth power. I concentrate on those builds. Jeff is a bit more into the gobs of power approach. But they all tend to be one-offs. I bet 95% of the distributors he does are for fairly stock applications, but as I said in a past MGB Driver article what he does with a distributor far exceeds what Lucas or Delco could do building thousands a day.

So can I fully explain the huge jump in horsepower on the TR6? No. But that's where we stopped. There wasn't R&D money for more. I'm not arguing with you, I'm just explaining the back story.

Warmly,
Dave

I'm not arguing with you Dave but... how?

There was obviously something terribly wrong with the -39hp Pertronix unit. Instead of trying another unit, points were installed. Instead of finding out what was wrong with the electronic unit it was instead simply reported as points gave 39 more horsepower than Pertronix. Objective reporting or...
Terry Ingoldsby
Calgary, Alberta, Canada   can
1971 MG MGB

Quote: Some of us aren't in the business of horsepower analysis on one-off engines, as customers won't foot the bill. Once their engine is developing the desired power, they tend to stop paying. I've said it before, Pertronix will mask problems on poorly functioning distributors, and will give improved dyno results on engines so equipped with poor distributors. On distributors with excellent clearances and advanced curves tailored to the cam and carbs, points will out perform Pertronix.

I keep asking - and no one wants to answer - are your tests based on Ignitor I technology or Ignitor II technology? Ignitor II should vastly outperform points.



Terry Ingoldsby
terry.ingoldsby@DCExperts.com
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