Mallory Dual-Point Distributor Conversion

There are a number of good reasons why you should consider replacing your Lucas distributor with a Mallory Dual-Point distributor.

First, accurate ignition timing is often one of the most overlooked areas of engine performance and tuning, and your car’s original Lucas distributor might just not be up to the task anymore. MG T series distributors will develop a rather incurable wobble between their two-piece body design, which, if present, will virtually assure incorrect ignition timing.

Check out your car’s distributor the next chance you get. Are the bushings worn? Are the mechanical advance springs weak? Is it difficult to maintain a correct reading? And is the vacuum advance even operative?

Secondly, does the idea of being stranded in the middle of nowhere by an electronic conversion send shivers up your spine? Electronic ignition systems may, in fact, be in use on practically every modern car built today, but if something goes wrong with my points distributor, I can still probably fix it long enough to get me home. Can you do that with electronic ignition?

So, to really get your ignition system back into shape, we offer the Mallory Dual Point Distributor, in either four or six cylinder versions, to fit most of the classic cars we drive today. The Mallory distributor has dual-point sets—one set leading and one set trailing, for more complete combustion and cleaner running. Mechanical advance is factory set, but can be manually adjusted to suit your engine’s state of tune. And because total advance is achieved mechanically, no vacuum unit is required. The one-piece housing is machined from solid aluminum billet and features an externally mounted condenser to prevent heat-related failures. Insofar as durability goes, these same Mallory units are a popular choice with the racing crowd. What was that old adage…”Race on Sunday—sell on Monday!”

Although complete instructions are included for installation with each distributor we sell, there are some finer points to the installation worthy of further explanation. In particular, the installation of the drive dog. I’ve spoken with a number of Moss customers who were discouraged by the fact that this was not done by Mallory. Keep in mind that drive dogs, or gears as the case may be, are generally unique to a particular engine, while the Mallory is designed to be used in many different types of engines. Therefore, you must re-use your old one or purchase a new one if possible.

Installation is not technically difficult, but if you think you lack the tools (or even the ability) to undertake this task, then take the new drive dog to a competent machine shop where they will charge you a nominal sum to install it. However, if you want to do it yourself, here’s how:

1) Take the old distributor from the car and remove the cap, rotor, and the breaker plate with points. Use a block of wood to support the shaft of the distributor and drive out the taper pin retaining the dog. Some models use split pins for this purpose, so be sure to note this before you proceed, and drive the pin in the correct direction if necessary. Withdraw the shaft, reinstall the rotor, and set it aside for the moment.

2) The drive dog has “offset” ears so that it can only be installed in the corresponding socket one way round, making subsequent installation and removal in the engine possible without disturbing the timing. However, the hole in the distributor shaft for the dog pin is centered, which makes it possible to install the drive dog on the shaft 180° off if you’re not careful. Use the old dog shaft as a reference for which way to install the dog.

3) Your two main objectives are: a) maintaining the relationship between the drive ears and the rotor, and b) maintaining the factory-specified end float of .010″.

Using the old shaft as a guide, place the distributor in a vise or similar, mark the hole center, and drill the hole using an appropriate feeler gauge or shim to maintain the end float while drilling. Then simply install the retaining pin.

This operation does not require absolute accuracy, but of course must be done with reasonable care. Minor inaccuracies of several degrees in one direction or the other will be invisible, since the distributor sits in a base which allows a wide range of rotation. In fact, most distributors can be rotated probably a full 75° or so, without interfering with the block. I’m not suggesting that you should be that far off, but it’s also unnecessary to build an exotic jig to accomplish this either!

Should you have any further questions please do not hesitate to call our knowledgeable sales staff for more information, or to order this Mallory distributor, which gives a hotter spark than the original Lucas unit and is a favorite among performance–minded enthusiasts.

—David Eichelbaum, Moss Technical Services