Smith 'Belvedere' 1910/11	Stuart Turner AE 1913	F.N. Sharpe original1928	Bond's Simplex 1931

It was however the designs and home built motors of the Innocent Brothers, Ken Williams, Stan Clifford and George Noble that would break the flash steam domination. All these motors were 30cc single cylinder, yet as the four-stroke IC motor eclipsed the flash steamers in the 30s, so they in turn were consigned to a supporting role by the highly developed two-stroke motor. By 1948 the outright hydroplane speed record had risen to 51.17 mph, held by ‘Faro’, a 30cc ‘A’ class boat and engine that had been built in 1935. A year later a 10cc ‘C’ class boat held the record at 70.1mph, nearly 20mph faster, entirely down to the use of a commercial two-stroke motor.

Mid 1930s four-strokes from the Innocent Brothers, Ken Williams and George Noble

The use of two-stroke motors was far from new as they had been utilised in boats almost from the word go, and as far back as 1925, Gems Suzor surprised all concerned with a 16mph run at the Grand Regatta. This was not fast in the scheme of things, but with an engine of just 17cc was enough to make people take notice. Suzor continued to develop the two-stroke theme, along with Andrew Rankine and his highly successful ‘Oigh Alba’ and a raft of others, such as messrs Row, Mitchell, Bowden, Buck and Duffield to name but a few, but it was George Lines and his ‘Sparky’ engine that really boosted the popularity of the two-stroke for boats in Britain, as here was a motor, simple to build, very fast, as his string of successes would attest to, and easily scaled up or down for A, B or C class racing.

The racing of model cars began some while after that of boats, and whilst some boats did use electric power, that source was much more successful in the early model cars, with many multi lane, rail track concessions running from the late 1920s. In the UK, clockwork and rubber bands were the more normal method of powering the cars used for racing, especially with the Cambridge and British Model Car Clubs that both ran regular race meetings.  The growth of tethered car racing from the late 1930s in the US was entirely due to the numerous small, IC engines that were becoming available. Several companies also produced casting kits for those that wanted to do their own thing, but this was no longer a necessity, hence the relative popularity of cars. The  banning of flying model aeroplanes and ending all official model boat racing during the second war in Britain provided the impetus that established tethered car racing in the UK as there was a large number of engines for which there was no immediate use and numerous enthusiasts that were no longer able to pursue their primary modelling activity.

Although Gerry Buck had recorded the first 100mph run with a car in the UK in 1948, this was with a home built engine, as many were at the time, but George Stone pulverised the hydroplane record, causing massive controversy in the process by using a Dooling motor imported from the US. Whilst some stuck resolutely with home built engines, the commercial motors were the route to success both with cars and boats. The Dooling in 5 and 10cc sizes, Hornet and McCoy would be dominant through to the end of tethered car racing in the UK and with the arrival of the Italian SuperTigre and Rossi, well beyond in tethered hydros. Arthur Wall recorded the first ever 100mph run in the UK with a tethered hydro in 1972 using a side exhaust Rossi motor but this was the last hurrah for this style of motor as from 1975 the British record has been held by OPS and later Picco powered boats. The use of commercial and imported motors was met with such antagonism in Britain that both the MPBA and MCA created classes and records that separated the home built and commercial engines in boats and the British and foreign motors and components in cars.  

The 40s saw  huge strides in engine development, especially in the States where racing continued throughout the war years. The decade started with coils, batteries, magnetos and spark plugs and finished with the ubiquitous glow plug, another American innovation.  Britain lagged someway behind, especially with the larger capacity motors, where several manufacturers, large and small, tried to produce engines to compete with the American products. Wilf Rowell up in Dundee, North Downs Engineering (NORDEC), Sid Smith from Chatham (Pioneer), Geoffrey Hastings in Worcester (1066 Products) and Ken Robinson (Speedwell) were just a few of those that produced 10cc motors to compete against the imports. The only real advantage that they held was that of availability, in the light of currency restrictions. With so many American servicemen travelling across the Atlantic, this did not pose too much of a problem for those determined enough.  Ultimately, the British motors were never quite powerful enough to beat the imports, but did find willing customers, but not in sufficient numbers to sustain most of the companies.

The 5cc class was again dominated by Dooling, although the British ETA found favour with many, especially in hydros, particularly as Ken Bedford of ETA was closely involved in racing and developing the engines, and that they were freely available. It was only in the smaller 2.5cc and 1.5cc classes where the British did make their mark, being internationally successful for many years, and this was almost entirely due to the efforts of the Olivers, father and son, from Nottingham. By the early 1950s, the twinshaft motors and single ended motors they produced, totally dominated these two classes. With the decline of car racing in Britain though, the few concerns that were still in business concentrated on the aeromodelling market, with ETA and Oliver having the same impact on the competition classes there as they did with tethered cars.

In the mid 1960s, the coming together of a number of engine developments created the style of engine that has been in use ever since in cars and hydros, making what existed up to that time redundant and later, collectors pieces. During the early 1960s Wisneiwski and Theobold developed the use of the tuned pipe with model engines, and such was its effectiveness that since then almost every motor used in tethered cars, hydroplanes and speed planes has used a tuned pipe. The initial problem as far as cars and boats was concerned was that these engines had all been developed for planes, so that the exhaust faced the wrong way, leading to some very odd looking models until manufacturers started producing front exhaust versions or those that could be assembled in either configuration such as the OPS. Oddly, one of the most popular engines in current use, the NovaRossi is still manufactured in rear exhaust form and has to have the hacksaw taken to it and turned round for car or boat use.

Ted Harris	Dickie Philips	Jimmy Jones	Terry Everitt	John DeMott

A single cylinder provided a degree of simplicity, but in full sized practice the move was to multiple cylinders and supercharging but this did not translate to model engines, despite numerous experiments. Not every motor is destined to be successful, and there have been some wonderful flights of fancy and engineering exercises that have given builders and other competitors immense pleasure. Many of these engines now rate as collectors items in their own right, such as the supercharged twins of Basil Miles and Bert Stalham and the supercharged two-stroke of John Duffield, that was still being run some 60 years after it was built.