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MG MGB Technical - pertronix distributor

pertronix has a distributor with the electronic ignition already installed. Anyone have experience with this distributor? Mine is very warn and I am looking at replacement/upgrades. Any suggestions?
Brian

Upgraded mine about a year ago with the Pertronix Flame Thrower electronic. You can buy it at Moss or Vicky B for a fairly reasonable price and it's easy to install. Also put in the Pertronix Flame Thrower Coil that matches up to the distributor. Also reasonably priced and both have been operating very well with no problems for the last year.
JCH Hibbard

Can you get a Pertronix electronic ignition to install in an 1963 Mk1 - an original +ve earth car that is now -ve earth. My initial search seemed to show a +ve earth version and then a -ve earth one for 67 models onwards.
Does anyone know what will work?
John
John Minchin

JC,
Could you tell any difference in Performance?
Brian

John,The negative earth Pertronix unit for the 25d4 distributor will fit your application. RAY
RAY

Brian, yes I noticed a increase in performance. John Moss is currently advertising positive and negative distributors from 62 on.
JCH Hibbard

look on the aldon site , i went for aldon 101by2and the elecrtonic ignition , it does not have any external amps and ballast recisters and the thing i like, if it lets you down you can swop it back in two minutes on the road side .i was adviced by peter burgess a few years ago and its the best mod ive ever done , its transformed the car ans worth every penny .
daz

Thanks Ray, Daz
I'll have a closer look
John Minchin

And JCH!
John Minchin

JCH,
Thanks, sounds like that may be the best way to go. A good replacement with a reasonable price and a slight tweak in performance. It does connect with two wires only correct? No external ballast?
Brian

Whether you need a ballast or not depends on the coil you have, not the trigger. Chrome bumper cars had a 12v coil and no ballast, rubber bumper a 6v coil with resistance wire contained within the harness as ballast. But any car could well have had a different coil fitted in the past, of course. The only way you can is to measure the coil primary resistance which should be from 2.5 ohms to 3 ohms for a 12v coil, or 1.2 to 1.5 ohms for a 6v. You also need to measure the voltage at the coil +ve or CB terminal with the ignition on and a ground connected to the coil -ve or SW. If you see 12v you have an unballasted supply so need a 12v coil. If you see less than 12v there would appear to be a ballast resistance in series which would need an appropriate low-voltage coil, but the low voltage could also be due to bad connections. The factory ballast is 1.5 ohms i.e. the same as the original 6v coil, which is why the voltage drops from 12v to 6v at the coil (the other 6v being dropepd across the ballast)

These are factory and Lucas Sport coils, other after-market manufacturers may have a different ratio of coil to ballast resistance, and they must be used together. The total resistance of coil and balalst should be in the range of 2.5 to 3 ohms.

Whilst an electronic trigger will give a performance improvement over knackered points, so will new points. I've never seen any independantly documented evidence that a good electronic trigger gives any better results than good points, which should last the recommended 10k intervals no problem (I've done 15k with one set as a test and didn;t have to adjust them at all in that time). You would be well advised to carry a set of points and condenser as spares, failure of electronic triggers isn't unknown, is sudden and total, and can only be fixed by replacement.
Paul Hunt

Thanks for the info Paul. I wouldnt expect much difference in a like new points set compared to one converted to electronic. In my case my distributor is very worn and sloppy. I am just looking for the most bang for my buck. Do you know of a reputable place to have a worn distributor refurbished?
Brian

Brian, try contacting Jeff Schlemmer at Advanced Distributors.http://www.advanceddistributors.com/index.htm He can rebuild your old unit to better than new and install a pertronix unit there if you wish. He'll recurve the unit to really match your engine.
Bill Young

Bill,
Thanks for the link!
Brian

Just installed a Pertronix unit built by Jeff and can't say enough good things about it.

One problem was the Jeff's distributor was 180 degrees off from mine but, once discovered, resetting the drive sorted that out and it's been bullet proof since installation. Stable timing, quick starting, smooth operation.....as I said, can't say enough good stuff about Jeff's work.
Joe Lucas Manitoba

Bill and Joe,

Here, here! Jeff's distributors are fabulous. Even if I had a new one from any of the other sources, I'd still send it to Jeff before using it. That's the only way to be sure it's curved correctly! So you might as well send Jeff your old one and be done with it.

FWIW,
Allen
Allen Bachelder

This thread was discussed between 16/07/2008 and 28/07/2008

MG MGB Technical index

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