The noise the twin-cam made was absolutely unique: a high pitched whoop that turned into shrill scream as it left the line. It had it's debut (at autocross or competition entire?) in the hands of Bernard Unett late 1968. At this early stage it was said to have 110 bhp and in the months that followed a lot of work was done to gain power and to develop the engine for road use.
Lynton Racing of Lynton Garage wanted to sell three stages of tune for the twin-cam unit:
In July 1969 a 1,000 c.c. Imp conversion costed £62.0.0
Hot Car 1969, April, p.52
There was a time when 100 bhp/litre was considered good for a specially designed racing engine. Lynton Racing reckon to get 130-140 bhp out of the 1 litre Imp engine when they have finished their present development work.
They have designed a twin-cam head for the Imp. In its mildest Group A form this gives 80 plus bhp and is flexible enough to be used on the road.The head features 4 valves per cylinder. This gives a very large throat area, but coupled with a high gas velocity and none of the problems of very large single valves (like: need for very strong valve springs; high cam loading; poor heat dissipation; etc.)
At £350 complete with inlet, exhaust and carbs, this is a very expensive road conversion, but in competition should give the fuel injected cross-flow Minis something to think about. Lynton offer a very full tuning service to the Imp owner. They have various stages of tune to fit in with the owners needs. They will convert Mk 2 engines to 1000 cc or 850 cc.
They have a complete suspension sort-out kit for Imp range. The car is lowered an inch all round with special competition springs. The camber is reduced to zero or one degree negative by using special modified stub alxle carriers. An anti-roll bar is fitted.
This kit costs £22 2s 6d, though all the parts are available separately.
All the gear for Imps is held in stock - Front radiators, long-range fuel tanks, special exhausts. Send a large SAE or drop in for details: Lynton Racing
Two articles on the twin-cam engine by Lynton Racing
Motor 1967, 7 Jan. (p. 52 ?) and 14 Jan.
Lynton 998 twin-cam Imp. - Cars & Car Conversions 1969, March. - p. 280
Reprinted in Impressions 1985, February
Lynton Imps / technical editor Ken Currie reports for the enthusiast. - Hot Car 1969, April, p.52. - [Hotline]
Lynton's Imp tested / David Hardcastle. - Cars and Car Conversions 1970, February. - p.175
The Imp family
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