Pertronix set up on a vintage Sun machine

Hello group, i have got an old Sun machine MDT-50 (vintage 1959) and i want to test a custom built Pertronix points replacement in a Marelli S129 type distributor. i have some reservations about the electrical setup. Does anyone here own and operate a Sun machine and has experience testing Pertronix? how do you power the points? is there any danger in damaging my strobe?
thanks for any help
Craig

 

The pertronix module is just a fancy electronic version of your points (an on/off switch), it won't harm anything if used on the Sun machine. The black wire coming out of the module will connect to where the points/condenser output normally goes, and then you just need to connect the red module wire to the 12v supply. You'll need to buy or build an adapter to allow the Sun to hold the large Marelli distributor body though, something along the lines of the Ford flathead adapter.

 

craig

you need a 12 V power source (car battery or 2 - 6 volt flashlight batteries in series) perhaps your machine is 12 volts. apparently the pertronix is sensitive to the correct voltage. negative on the battery goes to ground (metal plate on the pertronix or the distributor housing) and positive goes to the red wire. as you spin the distributor you will get 0 or 12 volts between the positive terminal of the battery and the black wire.

Hope that helps.

I am just about finished with a pertronix setup for a 365gtc4 distributor (euro single 12 cylinder distrubutor) that has 2 pickups (phased 30 degrees apart) in it and a 6 magnet trigger wheel (originally 4 points and a 3 lobed cam). Are you trying something similar? I would be curious to hear how you make out.

Stacy

 

He said it, and having just been here, I wanted to underline it. The black wire isn't ground and you need to ground the Pertronix unit for it to work.

I just put two Pertronix pickups in one of my 308 distributors and it seems to work very well, pulling harder to redline than it did with points. It is voltage sensitive. I'm having voltage regulator issues and the points never gave any problems with low voltage, but the Pertronix sure do. Sometimes the backfires are impressive! 4Webers here on Fchat had a small run of plates made for the 308 distributor that mount two Pertronix units. A bit of modification to the magnet ring with a Dremel tool was required, but it works!

Another note about the Pertronix - it appears to be a MSD type system. I get two sparks about six degrees apart at lower RPM. The box says it delivers twice the spark energy of points. I guess that's what they mean. Anyway, you'll see double when you look for your timing marks.

 

Thanks for the input so far. Is there anyone who actually owns and operates a Sun machine with experience at this task? Electrical hook up of the Sun to a Pertronix with a single and/or dual pick up. I would like to know the model Sun machine, the model Marelli, and the model Pertronix pickups you have succecssfully used.

The mechanical set up and experience with Marelli S85, S127, S129 distributors using points I already have. The Sun machine is an invaluable tool.

We all can visualize how this could be accomplished - ie hook up the red to 12v the black to the Sun ignition lead.

If the Pertronix pickup triggers a double spark, it would be visable on a Sun machine, yet no one has mentioned this. Is this really the case? What model pickup and rotor are being used to generate a double spark? Certainly Marelli and Ferrari are not needed at this task. Delco and Chevrolet might be a more common usage for Pertronix and Sun.

Anybody got Pertronix?
thanks
Craig

 

Are you sure the low RPM retarded 'points' are giving you that second spark some how?

 

My car doesn't have any points at all, let alone a second set. They all came out to put the Pertronix in.

 

Brian, glad to hear everything is working well. That is very interesting re: the double spark, I have an old Sun 1015 engine analyzer, with the analog scope, but I haven't seen any double-triggers like that, although maybe I just didn't see it since I wasn't looking for anything like that. Maybe that is something new since I purchased mine. All very interesting, a nice 'error' to have if it is one.

BTW, I still have a few of those adapter plates if anyone needs one.

 

Stacy, I just sent you a PM. I'm the one doing the conversion Craig is referring to.

 

Own, operate, and am well versed if you still need assistance...
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Hi Moku, yes i am still wanting confirmation on my proposed method of Pertronix testing, timing, phasing, advance setup, etc.

I successfully run a Sun MDT-50 (vintage 1957) on points style Marelli models S85, S127, S129. works great to check most aspects. I see you are using a 504.

Now i want to move on to Pertronix testing with the same Marelli and i have gotten a different story from each expert i talk to. My first task is replacing the four point setup in a S129C with 2 Pertronix. This Marelli is for a single distributor V12.

1) will the powered Pertronix damage my Sun? Are there risks? fatal mistakes?
2) what power source options should i consider for the Pertronix? Can i use a standard, small 9volt little rectangle battery as has been advised? i see you show a nice voltage supplier on the shelf, but maybe you have used other more crude methods?
3) I can check each Pertronix seperately, but it would be nice to check both at same time to allow most accurate timing/phasing. Can both outputs be hooked together to allow 12 strobes at one time?
4) advise on how to?
thanks for asking and i am greatfull for any advise
Craig

 

Craig,

1) Will the powered Pertronix damage my Sun?

Absolutely not. The ignitor is just a solid state set of points. The Sun machine has no clue what is hooked up to it. As long as it sees an interruption in voltage, be it from a set of points or a Pertronix, it will fire the strobe. Consider the strobe your ignition coil. As long as you stay within a reasonable voltage range all will be fine. See below.


Are there risks?

None that I’ve come across. My only caution would be that you make damn sure the fixture you use to hold the distributor in the machine is *solid* and well made. The flange you mount the distributor to wants to be good to the diameter you hold with the clamp arms. I use a 308 cam seal plate (that normally sits under the distributor) with a tube welded to it. I can post pictures and dimensioned drawings if you would like.

The only other risk would be that of spinning the thing up with a rotor installed. Don’t… some part of you *will* find that rotor sooner or later… guaranteed.


Fatal mistakes?

I sometimes set up the entire ignition along with the distributor to verify that all is working as it should. Cap, rotor, coils, plugs, etc. If you do so remember what kind of voltage you’re playing with. Be safe.


2) What power source options should i consider for the Pertronix? Can i use a standard, small 9volt little rectangle battery as has been advised? i see you show a nice voltage supplier on the shelf, but maybe you have used other more crude methods?

I’m not sure exactly how little voltage is required to make the Pertronix fire. My 504 does not require an external power source when used with normal points. It gives me 7.4 volts across the leads and is sufficient to fire the strobe. It is not, however, enough to get a Pertronix to trigger. In the past I have used everything from 12v car batteries, car chargers, you name it. I do enough of these conversions at this point that getting a good power supply became a necessity. For the $100 I spent it has served me well. I do have doubts about using a 9v battery but it may very well work. You’re surely not going to hurt anything by trying. Just for the hell of it I’ll spin one up when I get home tonight and crank the voltage down until the strobe skips. I’ll report back what I find. I can tell you if will be somewhere north of 7.4, though.



3) I can check each Pertronix separately, but it would be nice to check both at same time to allow most accurate timing/phasing. Can both outputs be hooked together to allow 12 strobes at one time?

I do this regularly with the 6 and 8 cylinder Marelli’s. You almost have to in order to accurately average lobe deviation (magnet phase). Pertronix rotors tend to be +/- 1 degree out of the box. Pisses me off…

One thing I do wonder about with your older Sun would be if the strobe capacitor will have enough time to recharge prior to being asked to fire again. This would be when running both ignitors at the same time and spinning the machine up good and fast. I guess it depends on what you’re running for a curve and where it’s all in by. Easy enough to find out…


4) Advise on how to?

Black wire(s) from ignitor(s) to positive lead on distributor machine.

Red wire(s) from ignitor(s) to 12v pos power source. (Battery, charger, power supply, etc.)

12v neg from power source to ground post on distributor machine arm or distributor body.

Negative lead at distributor machine to ground post on arm or distributor body.


That’s about it. I would play with one ignitor first and make sure you’re getting a good strobe prior to fooling with both at the same time.


Along these lines, I have offered to do a full article for BirdMan’s site on this entire procedure with detailed pics and instructions. I plan to take one of these Marelli’s from start to finish including disassembly, inspection, bearing replacement, advance mechanism overhaul and recurve, along with points setup and or Pertronix installation. I’m sure Jonathan will post when it’s online…

Any other questions feel free to ask away. Hope this has helped.

Rob

 

Rob
Great write up on how to connect the Pertronix to the Sun.

I do this exactly the same way. For power I use a small 12v motorcycle battery, but if you don't have one you can use a car battery with some small jumper wires.
I never thought about using a 9v battery, but who knows, it might work.

Brian Brown
Patrick Ottis Co.

 

Hi Rob,

Craig and I are doing this as project together. He has the Sun machine. I'll let him describe it's age and the model number. We're about 800 miles apart so this a UPS oriented project.

I have the Distributor, a 129C Marelli. Thus far I've used their MR-161 kit which is for a Dino and thus a good starting point for the V12.
The plate fits properly inside the dizzy but I'll be doing my own mounting holes for the plate to dizzy as the one (1) on the Mr-161 doesn't line up with anything. The reluctor was a bit loose so I've secured it with some thin aluminum shim that has a sticky backing. It's now a nice tight interference fit.

I am also changing the cap & rotor utilized as a part of the same project due to expensive and bad availability. The new cap is a Jag V12 cap and the rotor which matches that. This requires a 90 degree re-orientation of the rotor so all of that is getting aligned at the same time. The rotor is screwed to the adaptor which is affixed to the rotor shaft with a screw through the shaft.

This dizzy has a mechanical advance of only 10 degrees. With the very wide rotor contact (over twice the original) I don't think alignment of the rotor to the post is going to be a difficult issue.

I'm using a VW kit for the second sensor and you've now answered at least one of my questions regarding the second sensor mount. I wondered about manufacturing tolerances of the sensors and because of my concerns about that as well as accurately placing the mount holes for the second sensor I decided to allow for somewhat slotted mount of the second sensor. This of course is where the Sun machine comes into play.

So I'm curious as to how much adjustment allowance you find necessary. My guess is that if I do my best to accurately mount it on a bench with no Sun machine and leave 2 degrees adjustment in either direction I should be pretty safe. I plan on using a home made degree wheel, 12V battery and rotation by hand to get the first and second sensor location points. The idea being that Craig can adjust the second sensor while the dizzy is on his machine to achieve the 30 degree separation.

Have you ever experienced an off center condition with the reluctors gap to sensor calibration that resulted in a variation in degree timing from one lobe of the reluctor to the next? i.e. 28 - 30 - 31 ... etc.

Bob S.

 

Bob,

Let me get home and look up a few things before I comment. I've got most of the Marelli factory assembly drawings for these distributors and want to pull the one for a 129C. I also want to make sure of a few Pertronix details as well.

Back at you in a few hours

Rob

 

Brian,

Looks like we need to go for a ride.

I've got a fairly serious Guzzi Sport 1100... little R6's still kick my ass but at least I'm making the right noise when they go by me!

Rob

 

Thanks Rob, a great write up on Sun with Pertronix. Thanks for taking the time to respond. Your experience has taken my fears away.

Just for some more background - i called a man in Calif who operates a Thunderbird site - here is my email to Bob on this last week:
I called Gil Baumgartner in Calif
http://www.tbirdsbygil.com/Contact%20Information.htm
who runs Pertronix on his own old Sun. He says he has been doing it for a year with a little 9volt battery to power the Pertronix and it works just great.
okay one down.
i want one more.

Also Bob Masters at Sun distributor machine repairs/sales
http://www.distributortester.com/equipment_type.asp
was a great resource and had good info on this. Masters indicated that my machine (MDT-50)might struggle with this testing while a later 400 series, or 500 series Sun machine should have no trouble. Something about the voltage at the ignition lead. He also said the machine MDT-50 should not be hurt by trying this, but it may not fire the strobe.

Just another note on my Sun - I find the RPM indicator is not very accurate, so i use a handheld lazer RPM indicator and it seems to be way more accurate. At higher RPM, say 2000 RPM the machine indicator is 300 RPM off. I realize i could try and twist some adjuster pots, install better power to Tach, but the new instrument is much nicer. i also put new belt and wheel on and realigned all and it is smooth and quiet.
thanks for the technical help
Craig

 

First off, how the hell do I inline pics? I tried searching but came up empty. I don’t post that much and have no clue how to do it. When I use the upload attachments thing all my pics end up at the top of the page. Can anyone point me to a quick faq that will help me? It would be nice to be able to place pics where I want them… thanks!


Ok , from the top…


Very interesting voltage requirements… would you believe 4.4v is all that’s required to get an ignitor to fire nicely all the way out to 4000 distributor rpm? I set the machine at my normal 400 rpm setup speed and then backed off the voltage until the strobe quit. Who would have thought? Either way, the strobe was solid all the way to redline so it’s a safe bet that a little bitty 9v battery will do the trick for those that wish to use one. Can’t vouch for how long it’ll last though.

Correction to my previous post… -- I forgot that I have a SPDT switch in the circuit between the ignitors and the positive side of the Sun machine. The two black leads from the ignitors go to either side of the switch while the positive lead from the machine goes to the center pole. This allows you to quickly switch back and forth between the two ignitors. The Sun machine can’t distinguish two pulses per rev. Only one. Flipping the switch one way or the other gives you instant confirmation that your phase is correct between ignitors without having to shut the machine down and swap leads. Sorry about that, Craig…

Bob:

I use the new MR-181 plates in the 127 F and G’s as well as the 159 A, B, and C’s. The ignitors they provide are 05AB-V4’s. These are decidedly different than those I used to use when I was making my own plates but I can’t find that part number. The reluctor to ignitor gap is roughly 40 to 45 thou. The 181 plate comes with one (1) mounting hole as well. I could kill ‘em. I add two additional holes in the plate that match threaded holes in the distributor body. That seems to be all that’s needed to keep the thing flat and locked down solid. I would also *highly* recommend that you slot those holes 10 degrees or so in either direction so that you can phase the finished distributor to the motor it’s attached to. Taking all the various factors into consideration, more often than not you’ll find your nice new distributor jammed all the way over to one side of its adjustment just to get static at the crank correct. It just looks funky. Slotting those three holes allows you to quickly remedy that and leave the customer with a nicely aligned distributor base. Picky? Yeah, but these are very pretty motors we get to play with…

As far as ignitor to ignitor phasing goes, I call whichever one fires plug number one my “A” ignitor. I gap it, lock it down solid, and call it done. My “B” ignitor is slotted to allow for phase correction on the machine. The 181 plates come reasonably well positioned and I rarely have to slot the B ignitor further to get it set. Your method with the degree wheel sounds like it will work. Give yourself as much slot as you can without weakening the ignitor flange. 2 degrees may be too little. Be as accurate as you can and leave the rest up to Craig on the machine. You can also slot you’re A ignitor back or forward a bit too if you find yourself out of range on your B. You’ll be fine.

I’m not familiar with Jag caps but one concern does come to mind. You note that the rotor is nice and wide and should allow for adequate rotor to post alignment. Be careful here as you need to consider the potential for crossfire to the adjacent posts on either side of that nice wide rotor blade. Again. I’m not aware of the Jag design. If it’s similar to that of a 127F or G and has 2 separate post levels, you should be fine. If it’s like a typical Chevy distributor with all twelve posts in one plane I would be concerned. Just thoughts…

10 degrees of advance at the distributor for twenty at the crank? What kind of static are you guys running? This is leading to the next question which will be what are you doing with the advance mechanism and the curve itself. We’ve talked a lot so far about making it fire but not when.

Yes, I do occasionally see runout at the reluctor in relation to the shaft. Not much, though. Maybe a few thou at best. I seriously doubt that is what you’re seeing in the 28, 30, 31 thing. What I find *every single friggen time* with the Pertronix reluctors is phase deviation between the magnets themselves. Always roughly +/- a degree or so. Get the distributor in the machine and spin it up to about 400. Call this your setup speed and zero the advance ring on the machine to your “A” ignitor number one magnet. Now spin it up a bit further and note the phase differences. You’ll see each trigger point either retarded or advanced from where you want it. I normally note these and then move the reluctor around on the point cam to get the number one plug in the middle of that +/- range. You do *not* want the number one to be at either end of the range. You want to average, as best you can, the total deviation out. More on this whole concept when you guys have it in the machine and can see what I’m yapping about.

One last comment? Be nice to that distributor in your hands? I know *exactly* why you guys are moving to a Jag cap and fully applaud your efforts. Just remember how valuable that thing is and the fact that they are rather hard to come by in nice shape. If you can pull this off without having to modify the distributor you would make the Marelli Gods very happy. Me too. I say this in a *very* gentle manner…


Craig:

I’m not familiar with Mr. Baumgartner but, if he’s working on Tbirds, he’s ok with me! His experience with 9v batteries now seems spot on. In fact, it sounds as though we could cut one in half and still have things work fine.

Where did you score your laser tach? I’ve been wondering about the accuracy of the meter on my 504 and went so far as to temporarily rig up one of those big tachs you see all the kids put in their Civics. Didn’t work too well as it only had the option for a two pulse four cylinder…

In addition to Bob Masters, I would like to offer my own experiences with another gentleman in the Sun business, Mark Saunders. I believe another FChatter, Rob Garvin, might be able to add his voice in here as well. In short, if anyone is interested in obtaining a machine of their own, this is the man to call. PM me for info.

Ok, that should keep ya’ll busy for a bit.

Ask away if need be…

Rob

 

Rob,

This is dual plane cap very similar to all the other Marelli caps.
I don't believe the issue of the wide rotor really is one at all as there's a ~55+ degree separation between posts (60 on center) on each plane and the rotor is about 25 degrees wide. I could always trim it as well.

I wasn't going to slot the holes for the base plate as I still don't see
the need for it. Once 1A post is aligned why would I need to change it?
Please, if there's an issue here I'm all ears.

I have no intention of changing the advance curve. It's at the European specs now and I'm not into super tuning or untuning Lamborghini's design.
That part of the distributor's operation was confirmed as very good before I embarked on this exercise.

Now if I wanted ultimate performance I think I'd have gone digital with a crank trigger. I may yet regret that decision.

The 28 - 30 - 31 was a hypothetical issue and not something I've observed.

The only permanent change I might make to this dizzy would be to drill a couple of extra mounting holes which should not affect and future reversion to an archaic points and condenser system.

But now that I've put a degree wheel over the dizzy and started
rotating the shaft to see the open/shut points for the sensor
alignment what I've observed is that the sensor opens the circuit
(no voltage) for a 20 degree sweep then closes it for 10 degrees and
the cycle repeats.

I'm not a "points & dwell" guy but I think that works out to a dwell
angle of 10.

My points were such a mess (lots of broken and shorting springs)
that I never did analyze how they performed but my basic question is
given how this 4 sets of points system was supposed to work with
these dual coils is this 10 degrees of dwell going to give me
adequate spark?

Is this even an applicable question any longer?

Thanks for responding Rob.

Bob S.

 

>>>This is dual plane cap very similar to all the other Marelli caps.
I don't believe the issue of the wide rotor really is one at all as there's a ~55+ degree separation between posts (60 on center) on each plane and the rotor is about 25 degrees wide. I could always trim it as well.

Perfect. Sounds like you’re good to go. I just wasn’t sure of the Jag design and was wondering about the possibility of crossfire.


>>>I wasn't going to slot the holes for the base plate as I still don't see
the need for it. Once 1A post is aligned why would I need to change it?
Please, if there's an issue here I'm all ears.

I looked in my pile of Marelli stuff and don’t have a drawing for the 129C. Most, if not all, have three elongated slots in the distributor base that allow you to rotate the distributor and establish correct static advance. What I’m referring to is the positioning of the finished distributor while at that static advance. Are you pushed all the way to one side of those slots or the other? Or are you nicely centered in those slots and have room in either direction to make easy adjustment? Slotting the plate allows you to move everything in relation to the distributor base. You don’t have to if you don’t want to. I just find myself making this adjustment in 7 out of 10 distributors that I do. I’m thankful I slotted the plate every time.


>>>I have no intention of changing the advance curve. It's at the European specs now and I'm not into super tuning or untuning Lamborghini's design.
That part of the distributor's operation was confirmed as very good before I embarked on this exercise.

Again, sounds like you’re good to go. I know little, if anything, about what Lambo decides is right for their motors in terms of curve. But, I do know a ton about Marelli advance mechanisms and can attest to their general reluctance to perform. If you both are happy with its current state then that is a very good thing!


>>>Now if I wanted ultimate performance I think I'd have gone digital with a crank trigger. I may yet regret that decision.

From a performance perspective, yes, you will. There is no way in hell a 35 – 40 year old mechanical advance distributor will even come close to what a modern crank trigger will do. And the Marelli is a beautifully designed little piece. On the other hand, all my cars have Marelli’s in them and they run, in my opinion, extremely well with these Pertronix units. I don’t think about what I’m losing to a crank trigger because I’m very happy with the way it works as is. I also like a stock looking motor. It sounds as though you’re of similar mind. All good…


>>>The 28 - 30 - 31 was a hypothetical issue and not something I've observed.

You will soon enough. But not in the way you were imagining. More in the way I described in my previous post in regards to phase deviation in the reluctor. There isn’t squat I can do about it other than to design my own so I live with it. Yes, another point for the crank trigger…


>>>The only permanent change I might make to this dizzy would be to drill a couple of extra mounting holes which should not affect and future reversion to an archaic points and condenser system.

I'm just being a persnickety coot. I see so many of these distributors in various states of ill repair and modification I could scream. Again, I applaud your efforts.


>>>I'm not a "points & dwell" guy but I think that works out to a dwell
angle of 10. >>>Is this even an applicable question any longer?

6 lobes and 2 properly phased ignitors equals 12 sparks. I suggest you skip this part for now and continue onwards. Once you have it in the machine it will all become apparent. My gut says it’s going to work just fine…

Rob

 

Rob - I looked in my pile of Marelli stuff and don’t have a drawing for the 129C. Most, if not all, have three elongated slots in the distributor base that allow you to rotate the distributor and establish correct static advance. What I’m referring to is the positioning of the finished distributor while at that static advance. Are you pushed all the way to one side of those slots or the other? Or are you nicely centered in those slots and have room in either direction to make easy adjustment? Slotting the plate allows you to move everything in relation to the distributor base. You don’t have to if you don’t want to. I just find myself making this adjustment in 7 out of 10 distributors that I do. I’m thankful I slotted the plate every time.

Bob S. - Yes I have those three ears as well and I'll keep that in mind but
another "feature" of this dizzy is that it connects via a ~ 1.5" gear with a whole lot of fine teeth (46) so you have the ability to pull it out and rotate the entire mechanism a sight amount, numerous times.

Everything is extremely adjustable so there's lots of trouble (work) on tap.
Typical Italian engineering, if we can't machine it accurately then we'll make it very adjustable and put the burden on the mechanic. It's fun though ...

That adjustment slot looks to be a slightly less than 20 degrees and @ 46 teeth each tooth should be 7.8 degrees. My bet is that should mitigate the situation. At least I hope so ... Maybe I'll slot it anyway, just to maintain that Italian tradition!




Bob S. - I have no intention of changing the advance curve. It's at the European specs now and I'm not into super tuning or untuning Lamborghini's design. That part of the distributor's operation was confirmed as very good before I embarked on this exercise.

Rob - Again, sounds like you’re good to go. I know little, if anything, about what Lambo decides is right for their motors in terms of curve. But, I do know a ton about Marelli advance mechanisms and can attest to their general reluctance to perform. If you both are happy with its current state then that is a very good thing!

Bob S. - Those two bushings that sit on the posts and guide the advance mechanism through the slots were well lubed and are not terribly worn but I suppose I should replace them anyway. The slot they ride through seems perfect. There is only one spring and round tipped lobe per weight on this 129C. I know that some of the Ferraris have 2 per weight. The term advance curve is a misnomer here as it's a straight line. Maybe it's that "tractor" influence at work here ... ;>)

Where do you get your bushings?


Regarding dwell angle, a spec I do not have for the Lamborghini.
What do you think about this article: http://www.ratwell.com/technical/PertronixAdjust.html

 

Rob, Bob, and group, i found that the weights #12 supplied with steel slider collars #16 can be found at GTCP, but all other parts could not be had. i see a complete kit available from UK but it includes dual spring weights supplied with spring sleeves #14 which will not transfer to the stock bronze weights you get from GTCP - too large in diameter.

i also want spring pins #15 that i can trim to length, as i find the pins are too short in S85C applications. Is there a supplier for any of these items? 13, 14, 15?

also see -
http://www.huskyclub.com/tavspinterogeni.html
http://www.huskyclub.com/tavmarelliapplications.html
for addtional information i have posted for Marelli
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We have a male spline that fits to a mating female plug in the end of the cam. I forget the number of splines but each division works out to almost *exactly* the full width of the slot in the distributor base. You’re either at one end or the other if you screw up indexing the plate correctly. In addition, but to a lesser degree, cam timing also plays a role here. You can see why I choose to slot the plate. It’s very little work and solves the problem easily. I have no complaints as to the machine work in our Ferrari motors. No better or worse than the majority of what I’ve seen over the last 30 years. At least the 8’s.


The advance mechanism, although nicely designed, does have a few serious flaws. That and the complete lack of parts availability makes them a chore to get right. I’ll answer both of you here concerning the individual components thereof:

Yes, the 127’s and 159’s all have dual spring weights. I’ve learned to work with them and generally know what will get me to a good starting place curve wise. The straight line curve is a Marelli idea and is the same for the Ferarri’s. The stock curve in most of the 308’s begins at 1000 and is all in at 5. A bit too late for my tastes. With a bit of work, actually a lot, you can tailor the 4 spring setup to give a *very* nice curve that closely approximates what modern thinking says it should be. But it won’t stay there for long. You should bank on removing the distributor and rechecking it within several thousand miles. The lower portion of your curve will still be roughly what you started with. The upper portion will have gone to hell and you will find several more degrees advance coming in later than you want. See below for where I’m trying to go in resolving this trait.

I would stay far, far, away from the rebuild kits supplied by Superformance. I’m a diehard fan of theirs but this is one thing you don’t want to get near. The parts supplied in this kit are of extremely poor quality and I wouldn’t want you to waste your money when other solutions exist. This was my experience of roughly 18 months ago. They may, I hope, have better quality kits now but I’m not sure I would try again. Interesting that GT has the weights/bushings. I’ll have to call down there at some point.

#16 Bushing: Not available other than what you may have already found. I wouldn’t bother trying to replace them unless they are truly wasted. Chances are they’re fine. Lube well and leave well enough alone. See below for lube choice.

#15 Pin: Forget it… NLA. You will find that the contact area on these pins is your largest source of wear. That, and the corresponding area they rub against on the ID of the advance mechanism cup. (That’s what I call it at least). Wear in these two components is directly responsible for the majority of the trouble you will experience in getting a clean, smooth, curve. Dress the radius on the pin as best you can. If they have serious flat spots, and many do, you’re looking at a fair amount of time to make them usable again. The nicer you get these, the nicer your resulting curve will be. The ID of the cup is another story. You obviously have to work with what you have regardless of its condition. There will most undoubtedly be divots on the ID. My standard practice here is to attempt to smooth these out as best I can with varying grades of wet/dry paper and some WD as a lubricant. The divots are there to stay. Your object is to smooth them out so the mating radius on the pins doesn’t hang on an edge. The depth or severity is of issue, but you have the ability to work around this as you refine your curve.

If the ID is *really* bad I would try to find another and or send me the thing. I’ve sleeved a few of these in the past with exceptionally nice results. I’ve heard reports that some folks weld them up and re-machine but have no experience and shouldn’t comment here.

I also have a possible solution for the pins themselves but won’t have anything ready in your time frame. Think something along the lines of a roller lifter…

#14 Spring Cup: They should be fine. Leave them alone and lube them well. I don’t see many that are bad. All they do is contain the spring and center the outboard end of the pin.

#13 Spring: Century Spring has what you want. Search away…

http://www.centuryspring.com/Century/GateWayServlet?destination=MainCatalog.jsp

#? Spring Shims: You didn’t give these a number. These normally would go under the spring rather than below the pin head. At least on the 127’s and 159’s they are. They are 8 thou thick spring steel and are unobtainium. I have several styles of washer that come close to these but currently have a minimum thickness of .015. I would love a cheap source for these but haven’t had they time to look. I tweak the spring length instead for the time being.

#17 and 19 Shims: Don’t lose. Ever.

Also be nice to the rubber bumper on the shaft that the advance weights rest against. They are generally found to be brittle and will disintegrate with very little coaxing. The only solution I’ve found is a particular Viton heat shrink out of McMaster. Two layers gets you about 12 to 15 thou proud of what the bumper originally was.

Lube: Problem area but one with a nice solution, albeit an expensive one. You want a lube that will live in the heat and be as non-flinging as possible. You also want a super good extreme pressure lube for the pin radius. DuPont Krytox is the product. XHT-AC for mostly everything in the distributor except the pin faces. GPL215 for those. Again, McMaster. You don’t *need* this stuff to do the job. You want it, though, if the price doesn’t make you pucker up. I have yet to find lubricants of any sort that even come close to this product line. A tube of each will last forever.


Rob

 

How did you arrive at this choice?