Sports Model

Sports Model Description

The ‘dummy’ three seater sports car which had also been on the stand at the 1927 Motor Show had made an impact and created some interest. Two similar cars were built in 1928 with the short 8’ 6” chassis, but now with under slung axle at the rear. The first example had dry sump lubrication and what were to become the iconic ‘helmet’ type wings fitted directly to the brake back plates and so moving with the wheels. The second reverted to the wet sump engine with tourer type fixed wings. This car was on the stand of the 1928 Olympia show and was sold directly to the Maharajah of Patiala and exported to India.

The ‘Sports Model’ had a lower frontal aspect than the ‘T type’. The ‘Bertelli’ radiator was wider but lower than the ex. Bamford and Martin side valve radiator. Beautifully made in ‘German silver’ (a nickel silver alloy), they were very elegant and gave the Sports Model a low and ‘rakish’ look.

Being considerably lighter than the tourers, the ‘Sports Model’ had much better performance, and this was clearly the direction in which the company needed to go. Now with a conventional steering box, by Marles, the very low centre of gravity and the good weight distribution of the heavy rear axle and centre mounted gearbox gave the Sports Model wonderful handling, better than most other cars of the period.

Sports Model Derivatives

3 Seater

The first short chassis production car (chassis number S4) had coachwork very similar to the ‘dummy’ car first seen on the stand at the 1927 Motor Show. In the rounded tail of the coachwork a very small seat was fitted, with the passenger’s feet housed in boxes under the driver and front passenger seats. Because this unlucky passenger was sitting on top of the fuel tank this third seat was some 12 inches higher up than the front two seats. As a consequence the third passenger’s head would have been well above the windscreen and had no protection at all. It was however a very pretty body, and if the passenger was a small child or a dog, it would have worked well. The hood folded down behind the third seat.Orice £595

Three seater or ‘cloverleaf’ coachwork. Helmet type wings were mounted on steel ‘U’ shaped channel brackets bolted directly to the brake back plates. The dashboard was mounted separately from the bodywork, allowing the body to be removed without disturbing the dashboard or wiring. The spare wheel was mounted on the right hand side of the chassis on a tubular extension bracketed off the bulkhead. The windscreen opened out from the base. All ‘Sports Models’, like the ‘T-type’ had their bright work in nickel.

2 Seater

Five examples of the ‘Standard Sports Model’ were fitted with 2 seat bodies. Two had a slight rise in the bodywork immediately behind the cockpit (one of which had ‘T type’ wings mounted on brackets from the chassis). Two others had stub tails which dropped quickly from the rear of the cockpit emphasizing the short chassis. The fifth car had a stub tail with a lidded luggage compartment.

Sports Model Specification

Chassis
11’ 6” in length. The rear axle is underslung. The chassis tapers to the front, and to the back 8’ from the front cross tube, necessitating 5½” extensions to the rear cross tube to mount the rear springs. Six tubular cross members and one channel section cross member. An aluminium casting, the full width of the chassis, supports three brackets for the dashboard and the ½ “plywood firewall
Engine
The Renwick and Bertelli designed 4 cylinder overhead camshaft 8 valve engine. Dry sump, with additional scavenge oil pump mounted behind the pressure oil pump on a common shaft. An oil tank was mounted between the first and second cross members ahead of the front axle
Bore, 63.9 mm, stroke 99 mm, 1493 cc
Compression ratio: 6.5:1
Power: approximately 60 bhp at 4750 rpm
Torque: maximum approximately 55 lbft
Twin SU 1” side draught carburettors
Magneto ignition
Two ‘Autopulse’ fuel pumps mounted on the rear of the chassis, one for ‘main’ and one for ‘reserve’
Transmission
Aston Martin designed four speed crash gearbox with straight cut gears, constant mesh main shaft and layshaft, dog clutch 4th speed and reverse. The internally ribbed aluminium box mounted in the chassis, on three ’Silentbloc’ bushes is connected to the Bertelli designed worm drive rear axle (gears by David Brown) via shaft fully enclosed by torque tube. The clutch is ‘pull off’ Borg and Beck type. A self adjusting mechanism (by ratchet) is fitted
Ratios: 14.02:1, 8.74:1, 5.93:1, 4.66:1
Steering
Marles box, by worm and peg. It is conventionally mounted on the chassis with drop arm and drag link to steering arm on off side brake back plate
Wheels and tyres
‘Rudge Whitworth’ 52 mm x 21”, well base, 60 spokes wheels with 2?" wide rim, fitted with 4.50 x 21” tyres
Suspension
Half semi-elliptic leaf springs front and rear. ‘Hartford’ friction dampers
Brakes
14” aluminium drums with shrunk in steel liners and 1?” wide cam operated shoes mounted on a single pivot, actuated by rods. Perrot operated at the front. Handbrake operates all 4 brakes
Dimensions
Wheelbase: 8’ 6”
Track: 4’ 4”
Length: 11’ 8”
Width: 5’ 3”
Height: 4’ 6”
Weight: 17½ cwt.
Fuel tank capacity: 16 gallons
Performance
Approximately 70 mph
Price
£595
Coachwork
Three seater or ‘cloverleaf’ coachwork. Helmet type wings were mounted on steel ‘U’ shaped channel brackets bolted directly to the brake back plates. The dashboard was mounted separately from the bodywork, allowing the body to be removed without disturbing the dashboard or wiring. The spare wheel was mounted on the right hand side of the chassis on a tubular extension bracketed off the bulkhead. The windscreen opened out from the base. All ‘Sports Models’, like the ‘T-type’ had their bright work in nickel
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