Distributor issues

[Atrus]

Well, I've decided that I wanted to either get the Pertronix unit for my stock 25D, or get the whole new ignitor distributor by them.

As it's freezing cold, and I am going through withdrawl from not putzing around on the car, I mustered up some willpower, ran out to the garage, and yanked the distributor so I could make a good evaluation of it's condition.

I have a few issues that make me question which pertronix product to buy. The issues I have are below:

1) I snapped the vacuum advance line right at the nut on the advance unit. Anyone know where I can get a piece of the super tiny tubing so I can reconnect this properly?

2) I found one of the springs for the mechanical advance completely stretched out and just kinda floating around in there. I looked on Moss, it doesn't seem that they sell them. Is there somewhere to get the spring?

3) On the distributor body, where the clamp would hold it in place on the engine, there's a lip. It was noticeably bent inward. Not thinking, I tried to pry it back out into shape...yeah, I should have known cast aluminum wouldn't like that, and it indeed did not. So, I am now missing a piece of the lip, about .75" around the circumference. Is this going to cause me issues? I wouldn't think that it really would, perhaps an oil leak (although the o-ring should take care of that, correct?)

4) Shaft play - I notice none if I try to wiggle perpendicular to the shaft's axis. I do have some along the shafts axis, i.e. up and down in the housing. I assume this is normal and acceptable, we'd be worried about it having side play. Is this assumption correct?

Thanks in advance!!!

 

[Bugeye58]

Kevin, you may try a heating supply house, as some of the smaller diameter tube is used as control capillary tubing.
There's also a Parker store at, I think, Kelly and Groesbeck that may help.

For the spring, try Jeff at

https://www.advanceddistributors.com/

Wrap the entire circumference of the distributor lip tightly with masking tape, and then fill the cavity with epoxy. After it dries, smooth to shape, and you'll never have that problem again. I put a spacer between the ears of the clamp so it can't be overtightened, and cause that problem. A stack of washers on the bolt will do. There doesn't have to be much tension at all on the pinch clamp.

Vertical shaft play is no major concern, as long as it's not excessive. I would guess that most of mine have about .010'~.030" of vertical play. Some is required to allow for thermal expansion, differences in drive dog length, drive spindle thickness, etc.
Hope this helps.
Jeff

 

[Atrus]

That did help Jeff, thanks! I'll check all of that out. Makes me feel good, it seems to be in good shape, so I can't justify getting a new one, not to mention this way is much better on the wallet!

 

[Bugeye58]

Kevin, if there's an easy way out of these problems, that meet my engineering requirements for quality and durability, I've found most of them over the years, trust me! /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
We're going to have to hook up for a pint or lunch one of these days. I'm working in Auburn Hills, so it's only 20 minutes or so to your place.
Jeff

 

[Atrus]

Jeff,

Yes, sounds like a plan. Currently, I am in Southfield for work (hope to move to Auburn Hills at some point, looking for a new employer). Live at 18 and Van Dyke. So, I am sure we can find a suitable place to grab a pint.

One of my goals this summer is that I will be heading out to Dick O'Dowd's in Birmingham in the Healey. Seems suitable to me, Healey and a pint.

 

[Atrus]

So, Jeff got back to me (that was quick!). His reply:

Kevin, the springs varied wildly from distributor to distributor, so I don't sell them outright. I do however offer a recurve service to test your ignion advance and repair it starting at $34 including return shipping. A rebuild/recurve will run $69 plus parts - springs are included. If I were to sell you a pair of "original" springs, chances are very high that they won't work properly!

Here's my issue....I currently have the twin HS2's on the car. The plan is to go EFI...not sure if that'll happen for this summer, or if it'll be later (I am collecting parts and planning right now). Also, I do plan in summer '08 to rebuild the engine, cam it, head work, bore it, etc.

So, any suggestions? Honestly, for this summer, I just want the car to run! I wouldn't be opposed to having this done in the future, but it seems silly now to do it, use it for one summer, and then it'd have to be all remapped. For the $70 plus parts, plus another $80 for the pertronix unit, I am getting closer and closer to a whole pertronix unit.

 

[Trevor Jessie]

My opinion

It will only cost you another $35 when you get your engine redone (if and only if) you decide that you need a different curve.

You may end up driving with your current engine configuration longer than you plan.

 

[Atrus]

I guess my thinking is this....I want to put the pertronix unit in there. That's going to run me $80. To have Jeff rebuild it, at least $70. Then, I still need to fix the vacuum advance. Just Jeff rebuilding it and the pertronix puts me at $150.

I can get a billet pertronix for $170-$175 shipped. I'm thinking this is probably the way to go. I was just hoping someone would have a resource to where I can get a spring for cheap for now.

 

[Dave Russell]

2) I found one of the springs for the mechanical advance completely stretched out and just kinda floating around in there. I looked on Moss, it doesn't seem that they sell them. Is there somewhere to get the spring?

I was just hoping someone would have a resource to where I can get a spring for cheap for now.

Are you sure that the spring is stretched? The mechanical advance usually has two different springs in it. A primary & a secondary. The primary spring controls the first part of the advance. the secondary spring is longer & has some intentional slack. Only when the advance stretches the primary spring somewhat, does the secondary spring start controlling the advance as it's slack is taken up.
D

 

[dklawson]

If you do decide you're looking for springs, they aren't readily available. Cambridge Motorsports in the U.K. sells a spring kit for Lucas distributors. It's mailable to the U.S. in a blister pack envelope so shipping costs aren't bad. However, if you're doing this on a budget, you may want to buy a used dizzy off eBay to cannibalize for parts and/or rebuild as a replacement for your own.

Another (though more costly) alternative to the complete Pertronix distributor is the 1-2-3 Distributor. That unit has 16 switch selectable advance curves built in and it's all electronic. It won't look stock, but if you're going for a performance rebuild, the 1-2-3 will give you a trial and error way of finding an advance curve well suited to your engine.

 

[Morris]

How do you set up a "Trial and error" ignition curve safely and without melting down your pistons?

 

[racingenglishcars]

When it comes to distributor advance, there are no good general settings for non stock motors. And even still standard settings can be improved on for better performance and economy. A dyno test is the only way to get the proper advance curve and then the distributor must be adjusted to follow the curve found on the dyno.

One spring should be of finer wire and tight when stationary (not turning) One spring should be of thicker wire and loose when stationary. These two produce a two part advance curve. Combined with the maximum advance stop, the dizzy has three curves that work at different engine speeds.

See
https://www.teglerizer.com/mgstuff/advance_curves.htm
https://www.mgexperience.net/phorum/read.php?1,489531,490070


The standard system works pretty well as long as all the parts move freely. The engine can stand as much as 5 degrees out from optimal and still run well. Certainly not optimal, but well.

Special curves for more power / economy etc do nothing or worse than nothing by moving the timing further than 5 degrees out from optimal. Stay away from a "racing advance curve" if it is not made specificly for your engine or one very much like yours. (CR, cam, carbs, porting, carbon buildup on valves / combustion chamber, moment of inertia etc.)

As for the broken piece, it will not leak oil, just look a little tatty. As long as the dizzy will hold tightly in place it is fine.

Donn.

 

[Atrus]

Spring is DEFINITELY shot, it's completely stretched out to where it hardly resembles a spring at all.

At this rate, I am really considering the Pertronix complete assembly. Might not be absolutely optimal for a modified (or stock) engine, but I think it'll work well enough for what I am looking for. Perhaps I can find a junk dizzy at some point for cheap, and rebuild the stocker just to function as an emergency spare.

 

[racingenglishcars]

That sounds like good sense.

 

[dklawson]

Morris, my choice of words was poor.

The 1-2-3 Dizzy has 16 pre-programmed advance curves in it (no springs). These curves were developed by Marcel Chichak in Canada based on his work with A- and B-series engines. Basically, you select a curve based on a recommendation chart and if it meets your needs... leave it. If your engine isn't pinging and you believe there's more capability you move up to one of the more aggressive curves... stopping and going backwards if and when you hear pinging.

See:
https://www.tdcperformance.ca/
for more information.

 

[Atrus]

Looks interesting Doug...what's the price on one of these?

Woah...yeah, a little more than I wanted to spend. Just saw the links to the vendors.

 

[Hap Waldrop]

We've got a 1-2-3 dizzy on one of the vintage Midgets we race, it's a pretty neat unit, but costly, get ready to spend $300+.

 

[Atrus]

Yeah, Hap, it'd be fun to play with, but realistically, I think that's overkill for me.

I am thinking the Pertronix complete distributor will be the way I go. I've found them online for like $170-$175 shipped.

 

[Morris]

That thing is COOL! I want one!