Earlier this year I had cause to comment on a stainless steel exhaust pipe extrusion, for covering up the unsightly rusty ends that protrude from the rear of a lot of cars, and I suggested that stainless steel silencers were badly needed. It was not long before I heard from a firm in Scotland who are agents for a stainless steel silencing system patented in New Zealand, while one or two readers also sent me news of this firm, Stainless Steel Silencers, Ltd., of Ayr, who are specialists in stainless steel pipe work.
Anyone who works on cars or motorcycles must appreciate the benefits of stainless steel, and it can be used for all manner of things other than exhaust systems. It is gradually coming into use in production cars more and more, starting on simple things like it wiper arms windscreen surrounds and window trim, and Vauxhall, B.M.C., Routes and Ford all use it for small items, while Rover use it pretty extensively on the 2000 model.
It is interesting that the Vincent Motorcycle Owners’ Club have long been organising the making of exhaust pipes and handlebars in stainless steel for their big-twin machines, which have been out of production for many years, and their next move is to get stainless steel silencers made at an economical price. The question of price is the big drawback at the moment, but with wider use in all manner of industries, especially dairy farming household goods and breweries among other things, it is becoming a more economic proposition, and its use in the automobile world is increasing rapidly. Recently one motorcycle manufacturer changed over to the use of stainless steel for mudguards, which are formed on a press, and other things will obviously follow, such as wheel rims, headlamp nacelles and so on, which together with the wider use of aluminium for levers, chain-cases, wheel hubs, back plates, etc., should eventually result in a motorcycle more suited to our rusty atmosphere.
The use of stainless steel in the car world has unlimited possibilities and there are signs that engineers and designers are fitting it into their new designs where economically possible. Rolls-Royce use stainless steel silencers and until other manufacturers follow suit the Multifit Stainless Steel Silencer might interest owners who intend to keep their car for more than the life of the original exhaust system. Those people who buy a car, keep it warm and dry, and use for less than 10,000 miles a year are hardly likely to be interested, but anyone who does 30,000 miles or more a year, and uses their car all day and every day, might well be interested in paying more money for a silencer that will last an unlimited time, instead of buying a replacement standard item that they already know will last only a limited time.
It was this question of replacing rusty silencers with standard replacements, already showing signs of rust if not stored properly in the agents’ stores, that prompted a New Zealander to design the Multifit, with the idea of it being adaptable to all makes of car. While doing this he incorporated a new system of adjustable baffles, so that the silencer could he ” tuned ” for any condition the customer wanted; that is, silence, economy, power output, noise and so on.
The silencer is a basic unit, these units being capable of being joined together, depending on the engine to be silenced. A small car might make do with one ” unit,” while a big one could have three “units” joined together. These units are made in lengths of 5 in., 9 in. and 12, in., so a combination should be available for any condition. The inlet and outlet pipes lead into mild steel pipe-ends, purely for practical reasons, as the average garage mechanic probably cannot weld stainless steel, and it might be desirable to weld the silencer to a tail-pipe, rather than having a clip joint. The inlet and outlet pipes are mounted eccentrically in the end plates to facilitate mating up with a variety of exhaust systems. Special assemblies are available for unusual exhaust systems, such as the Volkswagen, but naturally cost rather a lot; the average simple silencer system could be replaced for about three times the cost of a standard mild steel silencer, the short life of which would already be known. In the Multifit system the perforated baffles can easily be opened or closed by hand, to vary the back-pressure and noise suppression, and as the “units,” or barrels, are merely expansion chambers, the whole silencer is very much lighter in weight than the average affair full of baffles, tubes or absorption material.
Stainless Steel Silencers, Ltd., of Park Street, Ayr, Scotland, are the sole licensees for this interesting product, which appears to be well thought out and well made, but time alone will tell how it stands up to mechanical wear and tear. Being made of chromium nickel stainless steel there will be no corrosion problems, either from internal condensation or outside water, salt, mud and other ingredients that make up British road surfaces during the Winter months.—D. S. J.