I bought one of these, Glendora dodge, had a lot of hassles; brand new, it had about .080 up and down clearance , which bothered me, but installed anyway . Then , after about 4K miles, it developed a LOT of side wobble, hit reluctor. I took it apart, NO GREASE at all at assembly; top and bottom bushing were totally dry and scored shaft , which tore up bushing, AND shaft ..junk. In thinking about it, timing will vary if shaft moves up and down as gear mesh below is curved....hmm..if it moves? Rotor pushes it down, but maybe not enough, and gear either pushes or pulls on it . talk about a subtle intermittant ..timing all over the place.

It also came with what looks like a thermoplastic black distributor cap; I never saw anything so flimsy and crummy. Found a good blue streak cap.

In parts blow out of a stock 67 distributor, it shows grease seals under weights, none of this on MP , no seal at all ,also, no oil cap to lube shaft. So bottom line, use old distributor and recurve it. MP one is junk, apparently mine was assembled by a moron; I kept thinking about that loose vertical fit..watch that spec! .

Advance in MP distributor is about 12 degrees , requires ~15-17 initial, seems high to get to 32 total w/o vacuum . that is about how much you would have to weld or braze pin slots in stock distributor to re curve, plus lighter springs. springs seem about same as MR Gasket 6$ kit

When replacing drive gears , the predrilled "one" cross pin hole was in different places vertically on different gears , several ways to look at that, but I think end of nylon gear wants to be even with shaft, as 67 was stock. this required a shim kit from MR Gasket to take up slop at top of top bushing , raises shaft up, and keeps it there with no adverse affects I could see; i think that is right way . (Takes up seal space!!) Mesh marks on old Nylon gear of worn stock distributor were in middle of plastic gear with shaft end even with gear end ..only thing i could go on. other way would drop shaft into block more, stick out of gear , not sure about that. Required redrilling of pin holes in new gear to get that 67 setup. I don't know why replacement gears I have had predrilled holes at different heights? Confused me like crazy ,but had 3 distributors to look at.

Info to think about...

PS don't let it roll off bench..that breaks your nice new gear (always lands gear down, per Murphy).

oops got this on wrong section..sorry

Lots of guesses/assumptions. You can save yourself time, aggravation, and money by checking here before proceeding with a parts purchase or installation.

The MP distributor comes with an advance "curve" (more of a straight line) totally unsuitable for street use.

Thermoplastic makes a very good distributor cap material as long as it's the right kind of thermoplastic. BlueStreak CH-410X cap is (glass-filled) thermoplastic.

Shimming the distributor gear to take up the space on the shaft is wrong; you need to redrill the pinion.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

dan I did redrill the pinion to get it exactly like stock 67 in relation to shaft . If I did not , shaft would hang out of end of pinion ; this was w DC distributor, not a 67 distributor, which has a seal and/or spacer washers (shim?) on top . If I put it flush like 67, with no shims there is .08 play, exactly the way it was shipped ; It is NOT "wrong" to put shim at top of top bearing to take that up.It might even be why distributor shims are sold, maybe, right? I might say it is "wrong" to stick shaft .1 further into engine which is what happens if you just ignore all that and redrill pinion to have close to zero end lash with no shim or seals.

I agree either thing can work.

My complaint about thermoplastic cap is I can deform it in my hands; it is like tupperware and it has no barriers on underside between contacts. Glassfilled plastic is rigid; this was an el cheapo flexible flyer .

As far as curve goes, weights would have to change shape , or size to move the way CG travels outward with RPM as all springs move by a spring constant, in response to force. Not sure what that means, or if DC weights are different, (they did not look different on any of 3 distributors i was working with..only slot length varied , but that part (advance rate )seems fine, if a little much at initial, as i said . One assumes DC can get that right, I would hope, but maybe you know more about it. i do not. Other than imprecise way to set vacuum aspect, advance seems to work out ..they tell you to measure vacuum etc etc, when just saying you need x degrees of vacuum ,like a shop manual does given 32 total in distributor and initail would at least get you in range

My point is poor quality overall of every part of it, especially no lube in bearings,and end play . Others may have bought one, not knowing any of this. I did.

Uh...no, the weights would not have to change to alter the curve. The spring selection and setup alter the curve, and the MP distributor comes with one ultra-lightweight spring only. That's what gives it the unstreetable advance curve.

One (and only one) thin washer belongs between the top of the pinion and the bottom of the distributor body. What's wrong is using additional shims to take up the slack created if you erroneously use the predrilled hole in a replacement pinion. Perhaps that's not what you were describing having done.

Injection-moulded thermoplastic caps generally don't have anti-flashover ribbing like the older compression-moulded thermoset ones.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

And why is this?? Better materials or cheaper production standards or a combination of both??




Greg

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http://www.youtube.com/hyperpack

I think it's because high-quality glass-filled thermoplastic has very good dielectric strength (electrical insulation/non-conduction properties)), and resists surface degradation of the dielectric strength better than thermoset materials. Given that even the top-quality (BlueStreak) thermoplastic caps don't have ribbing, and that they seem to work well without flashover even when very high power ignition systems are used, the theory seems to hold up in practice…!

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Well That's Good I just bought The Bluestreak cap and rotor and was a bit dismayed to find it was a smothie type cap on the underside.. now I feel a bit better about the purchase!

Greg

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http://www.youtube.com/hyperpack

yeah, anti arc over ribbing was never needed, it has nothing to do with cost . VS -6 , Stabl and male extender pills work too.

I think we need to clarify 'curve" which is rate of advance per RPM and the linear , too fast advance, which I agree the DC unit probably has . the stock 'curve is really two almost straight lines, as weights move sequentially ; The force a weight spinning generates is F = mA , where A is acceleration , in this case centripetal; linear with force or speed. A spring force is kxsquared , so changing springs only changes where it starts moving and how fast it gets to stops , not the shape of it , in a curve sense , unless spring has tapered wire. To get over that squared stuff, i think they pivot the weights over center so as force grows it has more or less force to pull springs in a leverage sense . So that may be "the Curve", but if you lighten spring, none of that works together as intended, and the weights fly out in a straight line advance curve, as a little force now quickly stretches springs ; in that sense, you change the curve shape but not a lot , more the rate it happens, so it is closer to straight looking .
.

I happen to agree that stock DC advance curved or straight, is too little and happens too fast, causing a big initial setting, like 15 or even 18 degrees, to get to 32 or 34 mechanical total. So what is answer? Not that something is wrong, rather what is right? It would seem an initial around 10-12 is good, and that says 20-22 crank in advance mechanism is needed ; as you know advance in distributor degrees is often stamped under slotted part of advance setup , and is usually like 16 17 or 18 ( 34-36crank) which works with near TDC initial.

Taking all this together, maybe what is needed is to leave stock springs alone, but limit travel in slots to get 20 -22 crank , which will also come in sooner anyway due to higher initial, and make it up to 32 -34 with 10 -12 initial ?

The DC distributor I got stock had two lighter than stock springs ; the Mr Gasket kit advise to use one light spring 'for street" two for racing only. So is DC distributor a racing only package/ They don't SAY that , selling them to all comers..like me .

I think I am going to try to figure out adjustable stops and leave curve alone, whether springs or weights , let them work as guys a lot smarter about it than us designed them at chrysler, but limit it to maybe 22 degrees , and set up 12 initial.

I hear you Dan,about DC 'curve" and think you are right. But someone somewhere must have dyno results or something that applies to a typical slight ly tuned slant six, showing advance in degrees vs torque at RPM say every 200 RPM ; that is what we need, and then match distributor to that.

otherwise it is elephants per cubit...

I did not say something clearly above; the Mr gasket set says use one light spring, leaving one stock spring, i think the lighter one, for street. two replacement lighter springs for race,;that is how DC came too, w two light ones . The mr G springs and DC springs look about the same; weight looks all the same.

I think you are right Dan, if I may infer; stock springs and stop travel seems best.

Anti-flashover ribbing was indeed very helpful with the older distributor cap materials, and it's still useful on spark plug insulators and on power pole standoffs and transformer towers and suchlike. John, I know you're new here, so please let me offer a small bit of helpful advice offered as a friendly welcome to the board: This is not like other internet forums.

The definition of "advance curve" is well understood, and most of us are familiar with how the mechanical and vacuum advance systems work. There's a great deal of good quality info here on the board about optimising spark advance curves for various slant-6 engine configurations and applications. Some time spent with the board's search function will enable you to get quickly up to speed. To get you started: you needn't figure out how to make the spring anchors adjustable, for they already are adjustable. Shoot for initial advance of 7 to 8 degrees. Happy new year.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Thanks dan, I am not moving spring anchors, I am talking about the slots, stopping the weights from traveling out as far . Where did spring anchors come from? Communication helps everyone understand, but reading the stuff we each send for content, is how we all learn. Not looking for how to, as much as looking to understand, which then makes how to easy. e.g., weight centripetal forces are linear with speed. So I agree, 100% we don't want to spread mis info..

Happy New Year to you, too; let's hope 09 is better..

John,

Send me your email and I will send you Doc's recurve manual. Dan is right,
do a search on recurve and you will mine and others experiences. I have mine dialed in perfectly for my build. You can't buy new MOPAR stock springs. You need to start collecting old distributors to find the spring combination you need. Don't worry about welding any slots unless your building a race car, just get the right springs and governor.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

I sell a spring kit with four differet rates for $25+3 shipping. Details are located on page two of "parts for sale"

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V8?? We don't need no stink'n V8!!

Mopar stopped using the side oil port with worm scored distributor shaft when the EI dizzy came into play.

FYI,

-D.Idiot

Hi, understand that (point type has oiler) but electronic stuff fits right in it ;it is a better quality piece, plus that oiler was apparently needed (see above).

Later engineers take away good stuff someone really smart figured out probably about 1940. Typical arrogance of some kinds of people that drives me crazy.--- probably got a free dinner off Chrysler for really dumb idea from a big mouth that saved 4 cents for the oiler. ;then bushing wipes out, costs them 200$ in warantee if it does.
The old guys knew what they were doing, and BS of the finest and newest most refined type doesn't change that all of a sudden. Bushings need oil, as in oil burner motor.

Ever try to get one of those bushings out? They recommend tapping it , and then pulling it with tap. How crude is that ? It is a standard .500 bronze /oilite bushing set .

I went after it later, kind of crude too, but worked, used snapped hack saw blade to cut a slot in it, then folded it in on itself, picked it out; cleaned up hole pressed in new one in a vise , came out OK.

When at first I could not get it out of DC/MP housing, (no .5 tap) I started looking for another way; stock 150,000 mile early (67) point distributor lying around had zip wear in bushings, with the oil provision ; MP lasted 4k. Obvious what to do; but MP had short slots which works well with 12 or 15 initial, it has about same 15 + crank at max, so got new nylon and put all that together with reluctor top ; and took out vertical travel with Mr gasket shims. any vertical travel will make the timing dance...a new fact I found the hard way. Left MP springs, there were two .

Still trying to sort out vacuum aspect, but need about ten degrees,i think, (44 total) and really liked what Ted sent me about keeping that vac advance away till 12-15" of vacuum. We ARE getting there. By understanding it .

Thanks guys...really.