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Got myself in trouble by converting my Mallory dual point to a Pertronix II Kit #9ML-141. This is a new kit out for dual points. I did this because the distributor was eating expensive points. Seems you can not email anyone at Pertronix. Problem is the engine ran good before the conversion but now will not start. With a charged battery it just pops. Checked the rotor height(ok), coil voltage is (13v), moved the timing slightly each way from center about 5 deg, tried ether (popped louder). Now I am out of things to do. Pertronix does not recommend using the ballast resistor which Mallory needed with their coil. So, I by-passed it. Pertronix does say you can run with it but it is not a good idea. Please Advise as I am getting ready for a Polar Bear Run Sunday. /ubbthreads/images/graemlins/confused.gif
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TR2/3/3A TR3 Pertronix conversion for Mallory Dual Point
- Thread starter bailee2
- Start date
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Re: TR3 Pertronix conversion for Mallory Dual Poin
[ QUOTE ]
Got myself in trouble by converting my Mallory dual point to a Pertronix II Kit #9ML-141. -------- Seems you can not email anyone at Pertronix.
[/ QUOTE ]
Here is a phone number you can try:
Corporate Office (Sales and Administration)
440 East Arrow Highway
San Dimas, CA 91773
Phone: (909) 599-5955
Fax: (909) 599-6424
Good luck,
D
[ QUOTE ]
Got myself in trouble by converting my Mallory dual point to a Pertronix II Kit #9ML-141. -------- Seems you can not email anyone at Pertronix.
[/ QUOTE ]
Here is a phone number you can try:
Corporate Office (Sales and Administration)
440 East Arrow Highway
San Dimas, CA 91773
Phone: (909) 599-5955
Fax: (909) 599-6424
Good luck,
D
Alan_Myers
Luke Skywalker
Offline
Re: TR3 Pertronix conversion for Mallory Dual Poin
Hi,
I agree with Don, I'd rather use Mallory Unilite module #562 to convert a dual point dizzy to electronic. It's a bit expensive, but I always worry about mixing various brands.
You can also use a single set of points in the dizzy and hook it all up to an HyFire VI-AL or one of the other Mallory CD boxes, along with a matching coil, for a hotter spark and should find the points last about 10x as long. I plan to convert my TR4 to full electronic, multi-spark ignition eventually. I'll try to stick with Mallory stuff throughout, hoping to avoid any compatibility issues.
/ubbthreads/images/graemlins/cheers.gif
Hi,
I agree with Don, I'd rather use Mallory Unilite module #562 to convert a dual point dizzy to electronic. It's a bit expensive, but I always worry about mixing various brands.
You can also use a single set of points in the dizzy and hook it all up to an HyFire VI-AL or one of the other Mallory CD boxes, along with a matching coil, for a hotter spark and should find the points last about 10x as long. I plan to convert my TR4 to full electronic, multi-spark ignition eventually. I'll try to stick with Mallory stuff throughout, hoping to avoid any compatibility issues.
/ubbthreads/images/graemlins/cheers.gif
G
Guest
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Offline
Re: TR3 Pertronix conversion for Mallory Dual Poin
[ QUOTE ]
Here is a phone number you can try:
Corporate Office (Sales and Administration)
440 East Arrow Highway
San Dimas, CA 91773
Phone: (909) 599-5955
Fax: (909) 599-6424
[/ QUOTE ]
I used a dedicated line at my office with unlimited nation-wide long distance, and a stop watch. The people at Pertronix NEVER let me talk to a tech. Wish I had had the above number to give them a piece of my mind, and tell them to put their product where the sun don't shine.
I realize many swear by the Pertronix system. To me tech support is everything. If I didn't have britishcarforum.com
I think I would be driving an Avalon.
Went back to stock.
Bill
[ QUOTE ]
Here is a phone number you can try:
Corporate Office (Sales and Administration)
440 East Arrow Highway
San Dimas, CA 91773
Phone: (909) 599-5955
Fax: (909) 599-6424
[/ QUOTE ]
I used a dedicated line at my office with unlimited nation-wide long distance, and a stop watch. The people at Pertronix NEVER let me talk to a tech. Wish I had had the above number to give them a piece of my mind, and tell them to put their product where the sun don't shine.
I realize many swear by the Pertronix system. To me tech support is everything. If I didn't have britishcarforum.com
I think I would be driving an Avalon.
Went back to stock.
Bill
Re: TR3 Pertronix conversion for Mallory Dual Poin
Hello Bailee,
I'm sure that this is too late but there is nothing at all wrong with the standard Lucas distributor and coil set up. The TR 3 engine is not a highly tuned unit and even if modified does not need dual point and electronic ignition, keep it simple.
Alec
Hello Bailee,
I'm sure that this is too late but there is nothing at all wrong with the standard Lucas distributor and coil set up. The TR 3 engine is not a highly tuned unit and even if modified does not need dual point and electronic ignition, keep it simple.
Alec
Alan_Myers
Luke Skywalker
Offline
Re: TR3 Pertronix conversion for Mallory Dual Poin
[ QUOTE ]
I realize many swear *by* the Pertronix system.
[/ QUOTE ]
Hi Bill,
I've heard more than a few other folks swear *at* them, so you are not alone in that. In fairness, it's hard to if the problems folks have encountered were installation-related, or spotty quality issues with the product, or if there might be compatibility problems with other components in the ignition. But, for those reasons, I try to stick with brands I know and build ignition systems out of matching components, rather than mixing various brands.
[ QUOTE ]
Went back to stock.
Bill
[/ QUOTE ]
Certainly, reverting to the standard Mallory points even temporarily would help identify if the problem lies with the Pertronix unit, or with it's interaction with the other system components.
You mentioned the Mallory points were wearing rapidly. If by that you mean the electrical contacts themselvers, there might be issues with your plug wires, dizzy cap, condenser, rotor or coil causing an odd or unusual voltage across them that's accelerating wear and tear.
If the wear you are refering to is at the rubbing block of the points, there might be some pitting or other problem with the shaft where they ride.
[ QUOTE ]
I realize many swear *by* the Pertronix system.
[/ QUOTE ]
Hi Bill,
I've heard more than a few other folks swear *at* them, so you are not alone in that. In fairness, it's hard to if the problems folks have encountered were installation-related, or spotty quality issues with the product, or if there might be compatibility problems with other components in the ignition. But, for those reasons, I try to stick with brands I know and build ignition systems out of matching components, rather than mixing various brands.
[ QUOTE ]
Went back to stock.
Bill
[/ QUOTE ]
Certainly, reverting to the standard Mallory points even temporarily would help identify if the problem lies with the Pertronix unit, or with it's interaction with the other system components.
You mentioned the Mallory points were wearing rapidly. If by that you mean the electrical contacts themselvers, there might be issues with your plug wires, dizzy cap, condenser, rotor or coil causing an odd or unusual voltage across them that's accelerating wear and tear.
If the wear you are refering to is at the rubbing block of the points, there might be some pitting or other problem with the shaft where they ride.
bobh
Jedi Warrior
Offline
Re: TR3 Pertronix conversion for Mallory Dual Poin
I agree with Alan. There are many factors involved in a failure of this type. To be fair to all involved, both our members and the manufacturers, you should test each piece to determine what is the cause. I don't mean a exotic labratory controlled test, but a simple test of each component in a way that will isolate the cause.
If the Mallory unit is eating points at a rate higher than normal. Troubleshoot the system to find the cause. Contacy Mallory for help if needed.
Once this problem is fixed move onto the next component.
Continue adding one component at a time until something fails.
Perhaps the problem has nothing to do with Pertronix. The Pertronix unit is pretty simple. Almost to the point that either it works when you install it, or it doesn't. If it doesn't then return it for a replacement.
On my cross country trip the engine died while sitting at a scenic overlook. Since we had installed the Pertronix unit less than 200 miles earlier, I thought it had failed. We removed it and replaced the original points. That didn't fix the problem. The new Lucas Rotor had cracked. I reinstalled the old rotor and the car started. Later I reinstalled the Pertronix and it's run ever since.
I understand Bill's frustration with his Pertronix. I don't recall if he took advantage of the warranty to try a second unit. (Bill, feel free to set me straight)
In many cases the wound is self inflicted but the newest part gets the blame. This is at best subjective evidence of a poor product. The real value in sharing our experience is to provide objective information. If the majority have problems with a product then the rest of us will cross it off our wish list.
I agree with Alan. There are many factors involved in a failure of this type. To be fair to all involved, both our members and the manufacturers, you should test each piece to determine what is the cause. I don't mean a exotic labratory controlled test, but a simple test of each component in a way that will isolate the cause.
If the Mallory unit is eating points at a rate higher than normal. Troubleshoot the system to find the cause. Contacy Mallory for help if needed.
Once this problem is fixed move onto the next component.
Continue adding one component at a time until something fails.
Perhaps the problem has nothing to do with Pertronix. The Pertronix unit is pretty simple. Almost to the point that either it works when you install it, or it doesn't. If it doesn't then return it for a replacement.
On my cross country trip the engine died while sitting at a scenic overlook. Since we had installed the Pertronix unit less than 200 miles earlier, I thought it had failed. We removed it and replaced the original points. That didn't fix the problem. The new Lucas Rotor had cracked. I reinstalled the old rotor and the car started. Later I reinstalled the Pertronix and it's run ever since.
I understand Bill's frustration with his Pertronix. I don't recall if he took advantage of the warranty to try a second unit. (Bill, feel free to set me straight)
In many cases the wound is self inflicted but the newest part gets the blame. This is at best subjective evidence of a poor product. The real value in sharing our experience is to provide objective information. If the majority have problems with a product then the rest of us will cross it off our wish list.
Re: TR3 Pertronix conversion for Mallory Dual Poin
All,
Thanks, Great answers! I used the Mallory because I got a good deal on it and my original distributor was shot. Since I have headers it looked like the performance thing to do.
I have been too busy to get back to the car but hope to finish trouble shooting the circuit on Wednesday night. I did not know that Mallory had a module for this distributor. Moss has this Pertronix kit in the new TR3/4 Catalog. So good lesson. It seems like you never find out the negatives about something like this until you get into it. I want to try and salvage this unit if possible and if it doesn't hack it I will send it back. Thanks for the Pertronix phone number too.
I will start looking at the ballast resistor circuit first. Perhaps the Mallory coil has to have one. I will also do a resistance check on the coil. Perhaps the whole problem is that you must also buy the Pertronix coil. Moss does not mention this.
I will get my 3 going again and soon. You guys are super though and good on you for responding. I will post a result.
/ubbthreads/images/graemlins/thumbsup.gif
All,
Thanks, Great answers! I used the Mallory because I got a good deal on it and my original distributor was shot. Since I have headers it looked like the performance thing to do.
I have been too busy to get back to the car but hope to finish trouble shooting the circuit on Wednesday night. I did not know that Mallory had a module for this distributor. Moss has this Pertronix kit in the new TR3/4 Catalog. So good lesson. It seems like you never find out the negatives about something like this until you get into it. I want to try and salvage this unit if possible and if it doesn't hack it I will send it back. Thanks for the Pertronix phone number too.
I will start looking at the ballast resistor circuit first. Perhaps the Mallory coil has to have one. I will also do a resistance check on the coil. Perhaps the whole problem is that you must also buy the Pertronix coil. Moss does not mention this.
I will get my 3 going again and soon. You guys are super though and good on you for responding. I will post a result.
/ubbthreads/images/graemlins/thumbsup.gif
Paul Slice
Jedi Hopeful
Offline
Re: TR3 Pertronix conversion for Mallory Dual Poin
I have a Pertronix setup in my Spitfire with the Mallary dual point dist.When I first installed it the car would not run, it would spit and pop when I tried to start it. I sent the Pertronix back to the place that it was purchased from, but when I got the replacement it did the same thing. You could reinstall the points and it would run correctly.
After some experimentation I found that the Pertronix unit required the timing to be advanced more than with the stock duel points. Try advancing the timing a little more and it may work for you.
This was 3 years ago and I have had no problems since the initial advance adjustment.
hope this helps,
Paul
I have a Pertronix setup in my Spitfire with the Mallary dual point dist.When I first installed it the car would not run, it would spit and pop when I tried to start it. I sent the Pertronix back to the place that it was purchased from, but when I got the replacement it did the same thing. You could reinstall the points and it would run correctly.
After some experimentation I found that the Pertronix unit required the timing to be advanced more than with the stock duel points. Try advancing the timing a little more and it may work for you.
This was 3 years ago and I have had no problems since the initial advance adjustment.
hope this helps,
Paul
Alan_Myers
Luke Skywalker
Offline
Re: TR3 Pertronix conversion for Mallory Dual Poin
[ QUOTE ]
I used the Mallory because I got a good deal on it and my original distributor was shot. Since I have headers it looked like the performance thing to do.
[/ QUOTE ]
Hi,
The Mallory Dual Point dizzy *was* a key performance upgrade in it's day and remains one of the few aftermarket dizzies available to directly fit the TR2-4A TRactor motor (okay, a drive dog needs to be fitted to the dizzy... but that's a simple process).
Actually *dizzies*/plural, there are a couple versions: one with vacuum advance, the other without, #2732001 and 2332001 respectively. There is also a third version, also non-VA, with a tach drive for aftermarket mechanical tachs, #2432001. These might be the only dizzies that are a direct fit to the TR motor. If anyone knows of one besides the Mallory and the original Lucas, I'd be interested to hear about it.
The original Lucas dizzy is pretty good, can be rebuilt fairly easily, and can be modified for non-vacuum advance and/or breakerless function. One of the "problems" with the Lucas is that there were quite a few different models, all looking very similar but with subtle differences, used in various TRs over the years. There might be some concerns if, say, a TR4A dizzy originally for use with the late cyl. head, exhaust manifolds and ZS carbs is fully compatible and interchangeable with a TR2/3 with earlier head design, 2 liter displacement, early exhaust and SU H6s.
The dual points help insure a strong spark and you sort of have a "backup" set of points installed full-time, in case one set ever slips or fails. A little system redundancy for the TR can't hurt. It's a very well made product, too. Service parts are a bit high, but then the Lucas stuff isn't cheap either. Plus, all Mallory dizzies are designed to be easily re-curved for centrifugal advance, to adjust for a specfic motor's needs.
Incidentally, the reason both vacuum advance and non-vacuum advance are offered is that VA is used with stock carbs (SU & ZS), but non-VA is needed with some aftermarket racing carbs such as Webers and Dellorto. The reason for this is there is simply no place to properly take-off vacuum from the Weber-style manifold, nor is it a good idea to create one (or more). The carbs are designed to run with each cylinder's intake isolated, for more precise tuning. A vac. port or ports on one or more of the manifold inlets will upset the balance (although the car will run and can be tuned to some degree to compensate).
I'm using a Dual Point on my TR4, but today I think I'd go with the Mallory Unilite dizzy instead (also avail. with or without VA, #4732001 and #4532001 respectively). In other words, I think I'd go straight to eliminating the points entirely. It's a little more expensive initially, but less than the cost of buying a Dual Point *and* later converting it with a Unilite module (part #562), plus there is the savings of service parts over the life of the dizzy.
Mallory also offers a variety of CD boxes, some with rev limiters and remotely adjustable advance, various compatible coils rated by RPM capabilities and breaker or breakerless design, power spike filters, plug wires, etc., etc. The same parent company that owns Mallory also owns Jacobs and Accel ignitions, so there might be some cross-over technology with those companies.
I know this sounds like an ad for Mallory, but, no, I don't work for them. Just a fan of their products!
/ubbthreads/images/graemlins/cheers.gif
P.S. Unfortunately, there is no similar, easy answer for the 6-cylinder TRs. The problem is the tach drive is integral with the original Lucas dizzy on those cars, and replacements don't have the drive, meaning it will be necessary to change to an electronic tach if using an one of the Mallory dizzies. Mallory doesn't list it in their catalog, but I'm pretty certain their dizzies that fit Jaguar 6-cylinder will work on TR-250/5/6, as well, albeit without a mechanical tach drive.
[ QUOTE ]
I used the Mallory because I got a good deal on it and my original distributor was shot. Since I have headers it looked like the performance thing to do.
[/ QUOTE ]
Hi,
The Mallory Dual Point dizzy *was* a key performance upgrade in it's day and remains one of the few aftermarket dizzies available to directly fit the TR2-4A TRactor motor (okay, a drive dog needs to be fitted to the dizzy... but that's a simple process).
Actually *dizzies*/plural, there are a couple versions: one with vacuum advance, the other without, #2732001 and 2332001 respectively. There is also a third version, also non-VA, with a tach drive for aftermarket mechanical tachs, #2432001. These might be the only dizzies that are a direct fit to the TR motor. If anyone knows of one besides the Mallory and the original Lucas, I'd be interested to hear about it.
The original Lucas dizzy is pretty good, can be rebuilt fairly easily, and can be modified for non-vacuum advance and/or breakerless function. One of the "problems" with the Lucas is that there were quite a few different models, all looking very similar but with subtle differences, used in various TRs over the years. There might be some concerns if, say, a TR4A dizzy originally for use with the late cyl. head, exhaust manifolds and ZS carbs is fully compatible and interchangeable with a TR2/3 with earlier head design, 2 liter displacement, early exhaust and SU H6s.
The dual points help insure a strong spark and you sort of have a "backup" set of points installed full-time, in case one set ever slips or fails. A little system redundancy for the TR can't hurt. It's a very well made product, too. Service parts are a bit high, but then the Lucas stuff isn't cheap either. Plus, all Mallory dizzies are designed to be easily re-curved for centrifugal advance, to adjust for a specfic motor's needs.
Incidentally, the reason both vacuum advance and non-vacuum advance are offered is that VA is used with stock carbs (SU & ZS), but non-VA is needed with some aftermarket racing carbs such as Webers and Dellorto. The reason for this is there is simply no place to properly take-off vacuum from the Weber-style manifold, nor is it a good idea to create one (or more). The carbs are designed to run with each cylinder's intake isolated, for more precise tuning. A vac. port or ports on one or more of the manifold inlets will upset the balance (although the car will run and can be tuned to some degree to compensate).
I'm using a Dual Point on my TR4, but today I think I'd go with the Mallory Unilite dizzy instead (also avail. with or without VA, #4732001 and #4532001 respectively). In other words, I think I'd go straight to eliminating the points entirely. It's a little more expensive initially, but less than the cost of buying a Dual Point *and* later converting it with a Unilite module (part #562), plus there is the savings of service parts over the life of the dizzy.
Mallory also offers a variety of CD boxes, some with rev limiters and remotely adjustable advance, various compatible coils rated by RPM capabilities and breaker or breakerless design, power spike filters, plug wires, etc., etc. The same parent company that owns Mallory also owns Jacobs and Accel ignitions, so there might be some cross-over technology with those companies.
I know this sounds like an ad for Mallory, but, no, I don't work for them. Just a fan of their products!
/ubbthreads/images/graemlins/cheers.gif
P.S. Unfortunately, there is no similar, easy answer for the 6-cylinder TRs. The problem is the tach drive is integral with the original Lucas dizzy on those cars, and replacements don't have the drive, meaning it will be necessary to change to an electronic tach if using an one of the Mallory dizzies. Mallory doesn't list it in their catalog, but I'm pretty certain their dizzies that fit Jaguar 6-cylinder will work on TR-250/5/6, as well, albeit without a mechanical tach drive.
Alan_Myers
Luke Skywalker
Offline
Re: TR3 Pertronix conversion for Mallory Dual Poin
[ QUOTE ]
With or without the DA?
don
[/ QUOTE ]
Hi Don,
DA?
/ubbthreads/images/graemlins/cheers.gif
[ QUOTE ]
With or without the DA?
don
[/ QUOTE ]
Hi Don,
DA?
/ubbthreads/images/graemlins/cheers.gif
Re: TR3 Pertronix conversion for Mallory Dual Poin
Paul,
Thanks. Did you have a Mallory coil? Are you using the ballast resistor? I will be trying out a few things Sat.
I advanced the distributor more and it starting hitting but not starting, it seems like an excessive amount of advance so I stopped.
Thanks, good idea.
/ubbthreads/images/graemlins/nonod.gif
Paul,
Thanks. Did you have a Mallory coil? Are you using the ballast resistor? I will be trying out a few things Sat.
I advanced the distributor more and it starting hitting but not starting, it seems like an excessive amount of advance so I stopped.
Thanks, good idea.
/ubbthreads/images/graemlins/nonod.gif
Paul Slice
Jedi Hopeful
Offline
Re: TR3 Pertronix conversion for Mallory Dual Poin
Bailee,
sorry it did not work. I use a Lucus Sport coil with out the ballast. I had to turn the dist. between a 1/4 and 1/2 an inch from its standard position before it would start, seemed a lot but when it cranked I checked the timing with a light and it was only slightly more towards advance.
good luck,
Paul
Paul
Bailee,
sorry it did not work. I use a Lucus Sport coil with out the ballast. I had to turn the dist. between a 1/4 and 1/2 an inch from its standard position before it would start, seemed a lot but when it cranked I checked the timing with a light and it was only slightly more towards advance.
good luck,
Paul
Paul
Alan_Myers
Luke Skywalker
Offline
Re: TR3 Pertronix conversion for Mallory Dual Poin
[ QUOTE ]
I was thinking dist advance. In yho is one better than another,or none at all?
don
[/ QUOTE ]
Hi Don,
Ahh, I think you mean with or without vacuum advance, right? All distributors have some sort of advance.
If running Webers/Dellorto or similar, the dizzies without vacuum advance are generally required. The reason is because there is no practical way to pick up vacuum from the intake manifold without upsetting the balance of the carbs and effecting the flow of the fuel air mixture through the manifold (I've done it, but it's generally better not). This type dizzy gets all its advance from centrifugal weights alone. Weights and springs can be changed to fine-tune and adjust the advance curve.
If running SUs or ZS or any other carb that has provision for vacuum takeoff at the manifold you should use the vacuum advance-type Mallory. A clue is an intake manifold that has a balance pipe between the individual runners, like *all* of the original TR manifolds do, along with some sort of vacuum connection. This type dizzy has centrifugal weights too, but those are assisted by engine vacuum to make advance settings under different engine conditions. The original TR Lucas dizzies all were vacuum assisted advance type (unless modified), so this type of Mallory is more of a straight swap.
As to operational differences, a dizzy *with* vacuum advance will normally give better gas mileage. The one *without* vac advance might be a little more "high performance". The one without vac advance may make it a bit easier to fine-tune the advance curve over the rpm range.
As I mentioned previoiusly, the choice of with or without vacuuum advance is available in either the dual point or Unilite electronic type dizzies.
An additional note, any Mallory dizzy for TR requires the installation of the drive dog on the bottom of its shaft. The old dog off the original Lucas dizzy can be swapped onto it or a new one can be purchased and installed. The dog is held in place with a pin, so a hole needs to be drilled in the dizzy's shaft. But, this isn't high precision work. I've done it with a hand drill using the hole already in the drive dog as a guide without any problems.
But, before installing the dog, consider that its orientation on the bottom of the shaft might be important to you. Note that the dog will only engage its driving shaft one way, because the tang and slot are both slightly offset. Before drilling the hole for the pin that holds the dog in place, check the orientation of the dog on the bottom and the rotor on top of your old Lucas dizzy, and use that as a guide if you want the plug wires to have approx. the original locations. In fact, this is an opportunity to make some changes, if you wish. On my TR4, I changed the orientation slightly to give slightly different orientation and help keep plug wires short, neat and well from hot surfaces. It took some fooling around with the wiring to figure out what I wanted to do with it, but I'm pleased with the results.
Hope this answers all your questions!
/ubbthreads/images/graemlins/cheers.gif
[ QUOTE ]
I was thinking dist advance. In yho is one better than another,or none at all?
don
[/ QUOTE ]
Hi Don,
Ahh, I think you mean with or without vacuum advance, right? All distributors have some sort of advance.
If running Webers/Dellorto or similar, the dizzies without vacuum advance are generally required. The reason is because there is no practical way to pick up vacuum from the intake manifold without upsetting the balance of the carbs and effecting the flow of the fuel air mixture through the manifold (I've done it, but it's generally better not). This type dizzy gets all its advance from centrifugal weights alone. Weights and springs can be changed to fine-tune and adjust the advance curve.
If running SUs or ZS or any other carb that has provision for vacuum takeoff at the manifold you should use the vacuum advance-type Mallory. A clue is an intake manifold that has a balance pipe between the individual runners, like *all* of the original TR manifolds do, along with some sort of vacuum connection. This type dizzy has centrifugal weights too, but those are assisted by engine vacuum to make advance settings under different engine conditions. The original TR Lucas dizzies all were vacuum assisted advance type (unless modified), so this type of Mallory is more of a straight swap.
As to operational differences, a dizzy *with* vacuum advance will normally give better gas mileage. The one *without* vac advance might be a little more "high performance". The one without vac advance may make it a bit easier to fine-tune the advance curve over the rpm range.
As I mentioned previoiusly, the choice of with or without vacuuum advance is available in either the dual point or Unilite electronic type dizzies.
An additional note, any Mallory dizzy for TR requires the installation of the drive dog on the bottom of its shaft. The old dog off the original Lucas dizzy can be swapped onto it or a new one can be purchased and installed. The dog is held in place with a pin, so a hole needs to be drilled in the dizzy's shaft. But, this isn't high precision work. I've done it with a hand drill using the hole already in the drive dog as a guide without any problems.
But, before installing the dog, consider that its orientation on the bottom of the shaft might be important to you. Note that the dog will only engage its driving shaft one way, because the tang and slot are both slightly offset. Before drilling the hole for the pin that holds the dog in place, check the orientation of the dog on the bottom and the rotor on top of your old Lucas dizzy, and use that as a guide if you want the plug wires to have approx. the original locations. In fact, this is an opportunity to make some changes, if you wish. On my TR4, I changed the orientation slightly to give slightly different orientation and help keep plug wires short, neat and well from hot surfaces. It took some fooling around with the wiring to figure out what I wanted to do with it, but I'm pleased with the results.
Hope this answers all your questions!
/ubbthreads/images/graemlins/cheers.gif
Offline
Re: TR3 Pertronix conversion for Mallory Dual Poin
[ QUOTE ]
The dual points help insure a strong spark and you sort of have a "backup" set of points installed full-time, in case one set ever slips or fails. A little system redundancy for the TR can't hurt. It's a very well made product, too. Service parts are a bit high, but then the Lucas stuff isn't cheap either. Plus, all Mallory dizzies are designed to be easily re-curved for centrifugal advance, to adjust for a specfic motor's needs.
[/ QUOTE ]
Just for the record here is how & why dual points were used. They are kind of obsolete now.
Single points:
When the points are closed, current flows through the coil primary winding & builds up a magnetic field in both primary & secondary windings.
When the points open, the magnetic field rapidly collapses & generates a high voltage in the coil secondary winding. (spark)
When the points close, current again flows through the coil primary winding & builds up a magnetic field.
Dual points:
Two sets of points are connected in PARALLEL.
They are set mechanically, nearly on opposing cam lobes, but one set is STAGGERED to open & close about 10 degrees later on it's timing.
When the first set of points opens nothing happens since the second set is still closed. Remember, they are connected in parallel.
When the second set of points opens about 10 degrees later, the coil primary circuit is interrupted & the coil fires.
The first set of points to open & close, now closes first & re-energizes the coil primary circuit.
The second set of points to open & close, closes later but doesn't affect the circuit since the first set is already closed.
The overall effect is to increase the point closed time (dwell) by about 10 degrees over what is possible with a single point set. This increased dwell time gives more time for the current to build up the magnetic field in the coil & increases the coil output at higher engine speeds.
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The dual points help insure a strong spark and you sort of have a "backup" set of points installed full-time, in case one set ever slips or fails. A little system redundancy for the TR can't hurt. It's a very well made product, too. Service parts are a bit high, but then the Lucas stuff isn't cheap either. Plus, all Mallory dizzies are designed to be easily re-curved for centrifugal advance, to adjust for a specfic motor's needs.
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Just for the record here is how & why dual points were used. They are kind of obsolete now.
Single points:
When the points are closed, current flows through the coil primary winding & builds up a magnetic field in both primary & secondary windings.
When the points open, the magnetic field rapidly collapses & generates a high voltage in the coil secondary winding. (spark)
When the points close, current again flows through the coil primary winding & builds up a magnetic field.
Dual points:
Two sets of points are connected in PARALLEL.
They are set mechanically, nearly on opposing cam lobes, but one set is STAGGERED to open & close about 10 degrees later on it's timing.
When the first set of points opens nothing happens since the second set is still closed. Remember, they are connected in parallel.
When the second set of points opens about 10 degrees later, the coil primary circuit is interrupted & the coil fires.
The first set of points to open & close, now closes first & re-energizes the coil primary circuit.
The second set of points to open & close, closes later but doesn't affect the circuit since the first set is already closed.
The overall effect is to increase the point closed time (dwell) by about 10 degrees over what is possible with a single point set. This increased dwell time gives more time for the current to build up the magnetic field in the coil & increases the coil output at higher engine speeds.
D