Topic: Solved - NEH 2113: Harker Special - 1934

[Carnut]

Identify this car and describe its builder, when it was built and its power source, for 1 point:

ANYONE FOUND GIVING ANSWERS GLEANED BY USING GOOGLE SEARCH BY IMAGE MAY BE BANNED FOR AN INDETERMINATE PERIOD!

[Carnut]

Experts?

[Carnut]

Pro's know?

[Paul Jaray]

.

[woodinsight]

Well done PJ - you just beat me to it!

[Carnut]

Well done PJ, you've got the right car.
But, just to repeat the initial question:

Identify this car and describe its builder, when it was built and its power source, for 1 point:

So, locked for you to complete the answers for your point!

Here are a couple more pics whilst we're waiting:

[Paul Jaray]

built in the thirties by a Mr.Harker, a Rolls-Royce engineer.
The engine:
It features two MG Midget blocks and heads mated to a twin crankshaft crankcase based on the Austin 7 design. The two cranks were geared together via a central output shaft.

W. E. (Edmund) Harker's interest in motor racing began in W-29 when together with his brother Ronald they were given an Austin 7 Ulster by their father as a reward for not smoking or riding motorcycles. The Austin was purchased through Rolls-Royce where they were both employed as premium apprentices so that they could obtain a trade discount

The supercharged Austin was raced at Brooklands and Shelsey Walsh. being a class winner at Shelsey many times and taking Class H records at Brooklands in face of works competition as well as coming seventh in the 1931 Double Twelve.

In 1930 he conceived and patented a plan to build a double Austin engine and commissioned British Engines Limited of Newcastle to build the crankcase. In it.,; original form the Mk1 Harker Special had two Austin 7 cylinder blocks and heads mounted side by side on a common crankcase and with a large Villier . supercharger between them. Two crankshafts each running in three roller bearings were geared together to form a 11/2 litre engine retaining file original standard bore and stroke of 56 mm and 76 mm. The H-section con rods had white metal bearings with specially made Y-alloy slipper pistons.

Tile engine was mounted in a crab tracked Austin 7 chassis with some Austin 12 components and a wheelbase of only 6 feet 3 inches, A stumpy two seater body completed what was a car with a particularly good power to weight ratio wit'-, something like 120 b.h.p. available and weighing under 10 cwt. The car's only appearance in this guise was at Shelsey in 1932 when it unfortunately overturned on the lower slopes during practice. throwing the passenger out and Harker received a blow from the steering wheel and had to he taken to hospital with broken ribs and lung injuries.

Undaunted from his experience Harker decided to scrap the original car an(] retained the engine which he mounted in a new chassis made to his design by Rubery Owen. The chassis consisted of a box section with dropped side members to lower the centre of gravity. An old Lombard AL 3 was also purchased and from this car Harker utilised the springs, gearbox casing and a few other parts. The I-section front axle with slightly unswept tubular extremities was manufactured by Bean Industries Limited and the original Lombard Perrot triple shoe front braking system was discarded in favour of two-shoe Perrot operated brakes in 13" drums. The rear axle consisted of a Moss straight toothed bevel drive with 16" rear brake drums. The gearbox ratios were 5.5. 6.7. 9.5. and 14 to 1.

The only recorded Brooklands entry in this Mk 11 form was the 1933 August B.A.R.C. meeting when it was entered in file Senior Mountain race and was placed 3rd behind the winning type 37 Bugatti of Cholmondeley Tapper and Eccles' Frazer Nash. The Harker lapped at 67.07 mph.

For the 1934 season Harker rebuilt the engine. replacing the Austin blocks and heads with racing type J4 cylinder heads supplied by Cecil Kimber of M.G. Cars. These were used in conjunction with specially manufactured blocks. The bore and stroke being those of an Austin Seven. 56 x 76mm. giving a capacity of 1.494cc. The overhead camshafts - one per block. operating overhead valves were driven by a long exposed duplex chain with a tension sprocket from the front of the engine. The Villiers Roots supercharger was driven from the front of the off-side crankshaft and it fed mixture to the outside of one block and between the two blocks to the inlet ports of the other block. The exhausts were treated the same way emerging to two tail pipes, one on each side of the car.

In this form the Harker Special was campaigned oil the Brooklands Mountain circuit where it ,won the Second Merrow Handicap at the 1934 B.AR.C. Whitsun meeting. Starting from the 31 second mark it won by 4 seconds. beating Sir Malcolm Campbell's scratch V-12 4 litre Sunbeam. The Harker Special averaged 67.5 mph for the five laps. with a best lap speed of almost 70 mph.

At the end of the 1934 season Harker decided to reduce the stroke to 55.25 mm and retaining the bore at 56 min. therefore providing an oversquare engine which would be competitive in the 1100 cc class. The Villiers supercharger was replaced with a Zoller M 160 which was driven at half engine speed from the front of the engine and delivered a boost of 30 lb per square inch. Two large downdraught S.U. carburettors fed fuel from an eight gallon tank located in the tail of the car and the supercharger was lubricated by a small oil tank located on the bulkhead. drip fed from a hand pump mounted on the dash board.

A modified eight cylinder Scintilla racing magneto was fitted which could cope satisfactorily with the engines rev limit of 8.000 rpm. The firing order was a normal 1,3,4,2 sequence for each cylinder bank and the firing impulses were evenly spaced by timing the crankshafts. The engine lubrication was by dry sump with an oil pump operating at a pressure of 100 ib per square inch. In this form the engine ran on methanol and a dynanometer test revealed that it developed 160 b.h.p. at 7.000 r.p.m.

RICHARD LEESON

[Carnut]

And that says it all!
Here's a picture of that interesting engine:

[grobmotorix]

The 1933 Harker Special: