Standard Avon Special powered by Ford and Riley!

This Standard Avon Special arrived at Holt station on the East Anglian Rally this year. Unfortunately the owner had disappeared, presumably riding on the steam railway, so we were unable to learn too much about him or the car.  By the time we returned to the Car Park the car had departed.

However, the car is definitely NOT Standard powered. It has a Ford Model A engine which appears to have been modified by Riley. If you study the photo carefully, you can make our the modifications: the Ford sidevalve engine of about 3 litres appears to have been modified so that the inlet valves are overhead operated by pushrods and rockers under the two "Riley" aluminium rocker covers. The new inlet manifold in black tubular steel can be seen feeding the head, with a Solex carburetter hanging from it and fed from an electric pump and fuel filter on the bulkhead

Interestingly, a "calorimeter" can be seen bolted into the front of the engine block, so it must be quite impossible to know the operating temperature when in motion.

If anyone else is aware of this modification, other applications of it or more detail of how it works, I would be grateful if you would let the webmaster know, and I will publish the detail here.

Footnote:

The Avon also appeared, briefly, at the Standard Triumph Marque Day, STMD at Prescott, see the later report

Within 2 days of posting, I received this reply from the owner:

Thank you for posting the feature.

You are mostly correct.

The car, a 1930 Avon Special No3 was purchased in Jan 2003 minus its engine and gearbox and displaying a lot of battle scars.

After much consideration and research (2 ½ years) it was decided that a 1929/30 24 horse (3.3 litre) Ford Model A engine and gearbox would be fitted keeping any modifications to a minimum and in period.

Like the missing Standard 9 engine the Ford unit is mounted on the front cross member and at the junction of the engine/box to the chassis rails, the pedals and hand brake on both engines are attached to the gearbox however the 9 steering box locates on the side of the engine so a left hand drive Model A steering box was fitted with right hand drive components and mounted to the chassis, turning a drag link box into a cross steer one. Unlike the 9 engine parts for the Ford are available off the shelf including period tuning parts.

The Riley 2 port conversion was developed by George Riley (USA) in 1929. It retains the use of the Ford’s side vale exhausts but uses pushrods in place of the inlet valves to operate 2 valves per cylinder. It has nothing whatsoever to do with Riley Motor Cars.

Downside to the Ford mod.

1)       The radiator as standard struggles to cope on days over 20 degrees.

2)       The 5.1 or 5.6 to 1 final drive ratio is wholly unsuitable for such a low revving engine.

3)       Fuel consumption is a little high. 

Once you have had some of England ’s best engineers and craftsmen sort out the above issues you will have a proper Vintage car that will effortlessly cruise at 70 mph for mile after mile (over 340 on Sunday alone) and be a joy to drive.

Mark Spridell