In 1959 Geoff Healey set out on an expedition to the Bonneville 
Salt Flats in Utah, USA to attack some international class records as a publicity exercise. They took two cars for the attempt, one of which was “based on an MGA chassis frame and fitted with a blown 950cc Sprite engine….The engine was blown by a Shorrock supercharger, a creation of Noel and Chris Shorrock, an eccentric vane type…” This, a quote from Geoff’s book “More Healeys”. He goes on to say: “To obtain the additional power required for these high speeds an ordinary ‘Shorrock’ low pressure, belt driven, super-charger kit is fitted. This gives a manifold pressure of 6 to 7 lbs per square inch and the engine will produce 78 bhp at 5500 rpm or 86 bhp at 6000”.
The EX 219 Record Breaker, its Shorrock supercharged engine and a list of the records achieved at Bonneville
[photos kindly supplied by Karsten Stelk]
So began the supercharging of Sprites and this is the reason the name Bonneville Sprite was attached to cars fitted with the Shorrock supercharger by John Sprinzel during his time at Grosvenor Steet and later at Lancaster Mews. These cars usually had the wire wheel conversion with Girling disc front brakes and 8″ rear drums making them also ‘Sebring Sprites’. John thinks the “Supercharged” badge came with the Shorrock kit for Sprites.
Below are a number of brochures and articles relating to the installation and maintenance of the Shorrock C75B on the Austin-Healey Sprite: (Click on image to open files)
[Several of the above articles courtesy of Ray English’s “Marque One”]
Examples of Shorrock-supercharged, “Bonneville”, Sprites below:
FEY 678 (left) is regularly campaigned by Alex Postan
and 2341 UE (right) is now owned by the Healey Museum (NL) (formerly by Ian Grainger, and earlier by John Baker, father of Clive)
Useful Links:
http://mk1-performance-conversions.co.uk/shorrock_archive.htm
http://www.shorrocksuperchargers.co.uk
[shorrocksuperchargers.co.uk was created by the late Ian Bishop who passed away in 2010
~ in his final weeks he installed a Shorrock supercharger in his wife’s Morris Minor pick-up.]
For spares, repairs & servicing I can recommend:
Keith Luck
supercharger.engineering@outlook.com