Press Release: Period-Correct, Perfectly Tuned, Vacuum Advance Units

Austin-Healey BN1-BJ8 Units

MGA Units

MGB Units

Triumph T2-4A Units

Triumph TR250, TR6 Units

To understand why these vacuum advance units are a “big deal” to Moss (and why we think you’ll see them as a big deal too), we need to explore their history: When our classic British sports cars were first being built, the factories were small by today’s standards, and they were dependant upon a large number of small shops where a limited number of professionals created specialized components and sub-assemblies. These small fabrication shops were the real foundation of the British Automotive industry in the early days. Many of the parts they made were built with lots of hand labor, and the attention to detail resulted in the creation of some truly unique pieces. The model was to produce as many versions of a part as needed to address the specific needs of a specific make and model. As the suppliers to the automotive industry grew, some of the traditions were simply carried on in a bigger factory with more people. Lucas in particular supplied a tremendous variety of voltage regulators, distributors, and vacuum units. As vehicles with slightly different requirements was produced, slightly different versions of the components made their way into the system. As time passed and a multitude of models were on the road, a corresponding multitude of replacement parts were needed.

Lucas, like any manufacturer, had to balance the desire of the engineers to have every component tweaked for each application and the need to make money. Complicated parts were replaced with simpler designs that were easier to manufacture. As newer designs came on line, they were incorporated into other assemblies, which is how one MG owner wound up with a brand new MGA distributor with a “late style” vacuum unit with a push-on (instead of threaded) vacuum connection. Wherever possible, the number of variants was reduced. You may find that 10 or 12 vacuum units were replaced by a single unit that worked fine with minor timing adjustments, but they looked different and frequently would not connect to the original vacuum lines. As the demand for some vacuum units declined, more consolidations were made in the interest of economy. When we were driving to work in our MGs, Triumphs and Austin Healeys, we were interested in replacement parts that worked and were affordable. Originality was simply not an issue. If the part was cheap and worked acceptably, the customer was happy.

Now that much time has passed, we’re seeing a shift in priorities of our customers. More owners are looking to rebuild their cars as period-correct as possible, “as it rolled off the assembly line.” Good news for Moss is our tie to the community of enthusiasts – some of whom are small-time manufacturers who love tinkering in their cottage shops. Just like when the cars were first being built, we’re now seeing a resurgence of super-specialized professionals who make a limited number of products yet excel in their reproductions. Usually it begins with a hobbyist who wants to recreate a perfectly correct piece for his own car, and then another person sees the part and asks for one for himself, and interest grows. In this case, we are working with a gentleman who enjoys the hobby, is an excellent machinist, and in his retirement has focused on recreating the vacuum advance units that disappeared long ago.

These pieces are hand-made and are completely historically correct and accurate to your specific application. Even the boxes the parts come in were correctly redone – down to the sticker identifying the part number. Of course these pieces cost a little more than the mass produced, standardized (but functional) replacements we’ll continue to carry. We’re thrilled to be able to provide parts that are as close to the original as possible, as they would be if they were still being made in those small shops scattered across the English countryside. It is now possible to have a vacuum unit that performs and looks like the original.

Founded in 1948, Moss Motors is the oldest and also the largest supplier of parts for classic British sports cars with warehouses on both the east and west coasts in the USA. Moss is a service driven company by virtue of its knowledgeable salespeople, responsive Customer Service Department, and available technical support. Moss products are supported by engineers, quality control, and R&D, and as a result, parts from Moss are backed by the best warranty in the business. Moss offers free printed catalogs for Austin-Healey, MG and Triumph vehicles. A Jaguar parts catalog is available online only. Shopping online is easy and convenient at For more information, visit the Moss Motors website or call 1-800-667-7872.

Moss Motors
440 Rutherford Street, Goleta CA 93117


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