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).
Road test report and specification sheet for an Alvis 'Speed Twenty' car.
| Identifier | ExFiles\Box 178\3\ img177 | |
| Date | 24th May 1932 | |
| FROM LA{L. A. Archer}/LV. C. to E.R. C. to HS.{Lord Ernest Hives - Chair} ALVIS 'SPEED TWENTY'. Through the courtesy of Park Ward we were able to try one of these cars, and fortunately it was fitted with an open body, (a saloon was not available). It was the open body built by Van den Plas for Messrs Chas. Follett Ltd, and which is to be illustrated every week in the 'Motor'. GENERAL SPECIFICATION OF CHASSIS. ENGINE - 6 cyl., 73 mm. x 100 mm., 2511 cc., RAC. rating 19.82HP., tax £20. ENGINE TO AXLESHAFT RATIOS: 4.5, 6.63, 9.59, 14.8. WHEELBASE: 10' 3". TRACK: 56". Weight of open car 26 cwts. WHEELS: 5.25 X 30" (18" rim.) ENGINE REVS: approx: 2200 at 40 MPH., giving a rolling dia. to the wheels of 14.5", which is about correct. MAX: SPEED CLAIMED: 88 MPH., which means 4840 RPM. CHASSIS PRICE: £600. We had this car on the road for 2 hrs. both in London traffic and on the North London by-passes. The writer drove part of the time. Rain was falling heavily and the road conditions were bad. ENGINE. The engine had 3 SU. carburettors, and the valves were push rod operated. One could drive in London traffic in top gear, but by far the best performance was obtained by the use of 3rd. almost continuously. However from dead slow in top gear the throttle could be pushed wide open, and the engine would pick up without hesitation. The worst engine period that one was able to pick out appeared to be at 33 MPH. in top gear, that is, 1815 RPM., although the engine was reasonably smooth bearing in mind the type of car we were testing, yet it had the peculiarity of being distinctly lumpy when opened up at speeds below 40 MPH., in fact, under the worst conditions this lumpiness felt like thumps on the underside of the floor. The demonstrator assured us that this was not the engine itself but an exhaust beat, and that it is cured by fitting a standard instead of a sporting silencing system. Under these bad driving conditions we were able to repeatedly do 70 MPH. (on the speedometer), and at that speed there still seemed to be a fair amount in hand. In 2nd., we revved the engine up to 4800., which is 41.MPH. (1) | ||