The Race Cars

[jonto]

Does anyone have any information on this car-
   
   
   Three were built for RAC Lightcar TT for 1500cc cars 1914, this race in the end was not run due to the outbreak of war. The car was described as being distinctly crab tracked, very wide at the front and narrow at the back. Suggesting there was much difference from standard catalog specs.

[Old Crock]

There seems very little written about these cars. Here’s two more photos of one of the cars, on trade plates, at Brooklands. The photos are from Sammy Davis’ diaries – ‘My lifetime in Motorsport’ – S C H ‘Sammy’ Davis (Heilbron). I think the engine was an Anzani (note the ‘low’ exhaust), and not a converted Fivet, the make being used in the production cars (and they weren't 1500cc anyway) – it may have been AC’s first use of Anzani engines. Note the primitive tyres, yet these are pneumatic as valves can be seen on the sideways shot.
   
   
   

[jonto]

"Thus, directly through trials, I at last attained to my first road racing , car, An AC, one of three which S.C. Westall, A. Noble and
   myself were to handle, though coming events, had we known it, were to cut short our hopes. Certaily that car looked odd, though never
   for a moment would we admit it.The front wheels were well out on a wide front axle, the rear wheels close in on a much narrower axle;
   the machine, in other words, was crab tracked. In front was a high radiator, quite unlike that of the conventional AC., which other details of the chassis closely followed; but there was a streamline tail in which sat the the fuel tank, the handle of a big air pump stuck out from the instrument board invitingly.
   We watched the beginnings of these cars every minute that could be spared, we fretted when the Calthorpes of more normal design were on the road long before our machines were recognizable, and then one day the first car stood in the works, run in , so they said, and ready for test. Anyhow, it made a most satisfactory noise, so Westall and I, narrowly missing the door doorposts to show the necessary dash, went off to the track. Alas, our much desired car seemed deader than the proverbial mutton, slower than the ordinary sports models. One or two tentative experiments revealed a considerable weakness in the brakes and a black moment, a burst at full throttle completely eliminated a big end bearing. Terribly chastened we took the car back, to be assured that all would yet be well, though the atmosphere was critical. Then a man we had never heard of shot another man in a country......" (S.C.H. Davies. Motor Racing. 1931).

[jonto]

The tyres would be high pressure beaded edge, running at about 60psi, the pressure holding the tyre beads in the rolled over rim edges. They were normal equipment until superseded by the straight sided tyres and rims around 1923. Solid tyres went out of favor in the 1890's except for commercial use.

[jonto]

The French built Fivet engine had a fixed head and integral exhaust gallery, the exhaust pipe bolting to a flange at the rear of the block, so I guess that rules out an overbored Fivet engine in the 1914 TT car.
   
   
   The four cylinder side valve Anzani engine was not around in 1914, Gustave Maclure the designer putting pen to paper after the armistice when the aero engine contracts were cancelled. There might be a description of the 1914 TT car in the contemporary press.

[Old Crock]

The plot thickens....I'm now curious which engine was used, and to which manufacturer AC turned?

[Jam2]

I think the Fivet engine in the 10hp cars was 1096cc, I understood that the 12hp cars of 1327cc were also using the Fivet engine, presumeably bored and/or stroked.  I don't know enough about the Fivet engine, but perhaps they were able to bore it out that little bit more?  As the racing was always a means to advertise, I would have thought it unlikely that they would have used a different manufacturer than that used in the standard cars.

[Flyinghorse]

I also suspect it was a Fivet of some description having just looked at the little 1952 book "history of AC cars" which covers this car in Chapter 5 and comments on it running the 4 big ends.Chapters 2&3 discuss the Fivet engine and it having to be sourced out of the UK as no suitable engines were available in the UK and the switch from cone clutch to Disc and later (1919?) on to using Anzani engines.
   Chapter 6 covers the 100miles within the  hour run at Brooklands in a 1.5litre in 1922.
   
   Regarding the exit of the exhaust,is there not two pipes coming out of the bonnet near side?  I would not put it past them having and exhaust exit front & rear to improve performance. The bonnet of the 1914 car is much longer than the fivet shot above so perhaps this could be accommodated.
   A 1924 swift I had came with 3 Swift engines all from 1924/5 and each had a different exhaust exit (on front cast in,one rear cast in and one down as a bolt on manifold)
   
   Graham

[jonto]

It was common practice on early engines to take the exhaust from the rear of the engine, then by the mid 20's manufacturers tended to move the take off to the front after having set a few floor boards on fire :-)
      Racing engines however tend to have horizontal takeoffs one to each cylinder and a straight pipe down the side of the car at cylinder head level.

[B.P.Bird]

Intriguing - could the '100 miles in an hour' 1.5 litre engine have been a development of the engine in this 1914 racer ? Weller and A.C. had been making engines since the earliest days so why not build engines for the racers ? I agree that the low exit height of the primary exhaust pipes from the bonnet does lead to a first impression of a side valve motor, but if you look at the sump it protrudes way below the chassis so maybe the exhaust height is misleading. Could the 1914 racers have been using the first version of Weller's d.o.h.c. 1.5 litre four cylinder. Total speculation on my part with no evidence.....

[jonto]

Yes I agree I think the engine was a Weller design, the beginnings of the post war OHC engines. Look at the front view and you can see that the starting handle shaft is below the chassis frame in what looks to be a subframe, so the engine is mounted low in the chassis, the crankshaft below the main chassis frame. The transmission looks to be special too, narrow track, the only reason for this would be a solid diffless axle. Enlarging the side view, the rear springs appear to be angled inwards, the brakes look to be contracting band brakes, Weller was probably trying to work out how to brake the live rear axle ends.
   There exists a portfolio of drawings in the Science Museum collection, its just possible there maybe something there-
   http://http://discovery.nationalarchives.gov.uk/download/GB%200069%20AUTO
   There could also be a description in the contemporary press, the RAC Lightcar TT would have had some coverage.

[jonto]

A rare rear view of an early car, (W.J. Brunell photograph).
   
   
   You can see the transmission of the 1913/14 period, with substantial cast aluminum axle tubes supporting the spring mounting and the hubs/brakes. Just a tool locker at the back, no dickey seat, I think that came along in 1921 at the beginning of the Edge period.

[jonto]

A team of three cars was intended to compete in the TT, there would have been parts in various stages of completion, but it seems everything was behind and untested, its likely that only the one car was completed, its performance was poor and Weller was probably relieved when the race was cancelled. However the car would survive the war to try again....

[Old Crock]

quote:Originally posted by jonto
However the car would survive the war to try again..

Hi Jonto - if you are correct that the 1914 car used the Weller race engine then some serious changes subsequently took place following the war, not least (a) that Weller’s four cylinder race engines (in Hawker's early 1921 racer and also Joyce’s later ‘100 miles in an hour’ car) had the carbs on the left and the exhaust on the right side and (b) I believe these used a 1500cc wet-liner engine derived from Weller's work, after the war, on the 'Six'. Therefore, the engines would had to have been so changed/modified they might not be considered remotely the same.

[jonto]

Just a new camshaft would be all that was needed to change sides on the head, a new head would be a lot more work but would have been done if thought necessary.