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Letter from Alta Car & Engineering Co. Ltd. regarding their 2-Litre supercharged racing engine and AC 9 bearing material.


Identifier  ExFiles\Box 116\3\  scan0021
Date  22th April 1939
  
TELEPHONE—ELMBRIDGE 3157.
C.T.S. 1020a
TELEGRAMS—ELMBRIDGE 3157.
ALTA CAR & ENGINEERING Co. LTD.
Directors —
G. {Mr Griffiths - Chief Accountant / Mr Gnapp} TAYLOR.
L. TAYLOR.
April 22nd, 1939.
FULLER'S WAY,
KINGSTON BYE-PASS,
SURBITON.
Your Ref. Experimental. Rm {William Robotham - Chief Engineer} /CTS {C. Trot Salt - Carburation} /1/MH. {M. Huckerby}
Our Ref. GT.LV.

Messrs. Rolls Royce, Ltd.,
Derby.

Dear Sirs,

With reference to our previous correspondence in September of last year with regard to your AC 9 bearing material, we enclose herewith a sketch showing the arrangement of the connecting rod and crankshaft, also a print of the connecting rod.

The engine we now wish to try a set in the big ends is one of our two litre racing engines and we had thought of getting them fitted for a race in the near future. We should like to use our standard rod with a bored out big end if it will allow of this operation to a sufficient extent.

The engine is a 2 Litre supercharged four cylinder unit with a three bearing partially counterbalanced crankshaft. The boost pressure is 18 - 20 lbs. guage, the compression ratio 7.8 to 1, and the usual fuel 97% Methonal.

These engines give 250 B.H.P. at 5800 r.p.m. and the power curve is fairly flat until it reaches 6500 r.p.m., the bore and stroke are 79 m.m. x 100 m.m.

The oil is Castrol R with Collodial graphite added; the pressure, neglecting centrifugal effect 120 lbs. per sq. in. Tecalemit felt type filter is used, and in addition the crank shaft acts as a centrifugal filter, the shaft is made of Nitralloy.

We should be very glad if you could give us some information on the following points:-
  
  
From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).


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