A Cautionary Tale

AFTER AN EXCITING drive at the Castle Coombe Circuit in Wiltshire, Tim Bishop has asked me to relate his experiences in the hope that someone may be able to explain what really happened when he stopped somewhat prematurely at Camp Corner in front of the pits.

Tim has been a member of the Hampshire area for a number of years and as his job entails a month at a time bobbing about in the North Sea, he likes to enjoy his leisure time to the full. To this end, some four years ago, he decided to convert his Grinnall 2+2 TR7 (possibly the first) to V8 spec.

Initially this comprised the standard SD1 engine with a 390cfm Holly, uprated brakes and lowered stiffened suspension running on 14 inch rims with 205/60 front and 225/60 rear tyres. However, after participating at a number of hill climb meetings, Tim decided to increase the output from the engine so 10.5:1 pistons were fitted together with a 228 camshaft and the complete unit tuned on a rolling road. Result - 158bhp at the wheels and a very tractable car.

Since then, Tim has participated in hill climbs whenever work permitted with a good degree of success.

I think that with this background Tim should be well suited to 'non-competitive' laps at Castle Coombe. This proved to be true last year where he completed about 20 laps without mishap until he spun on the last lap, at Camp Corner, due to a late gear change. Tim freely admitted that this was a mistake on his part.

This year with more hill climbs to his credit, Tim again went to the Action Day. Perhaps life was a little more competitive as the Lamborghini Countach he was following was proving difficult to pass, but after 17 laps the limits to which one can drive had already become very apparent. This was the situation when again approaching Camp Corner. After this length of time the brakes were beginning to fade and negotiating corners required maximum concentration, so when the back end began to slide it was a question of using opposite lock, watch the power on the right foot, feed the steering through as the back straightened and continue to press on. This was fine until the car suddenly decided to spin the other way for no apparent reason, continue backwards at high speed across the grass and hit the tyre wall with some expensive damage to the offside plus a badly bent nearside trackrod.

Yes, I know what you are all saying - Tim had overcooked it again. I must admit that it was my first reaction, but I have since looked at photographs taken by an independent professional photographer. These pictures clearly show that the nearside front wheel was about 60° out of alignment BEFORE the bar hit the wall. So what happened? One possible theory could be metal fatigue of the trackrod following prolonged heavy cornering on overside tyres both at the hill climbs and the track caused it to bend - if so perhaps this could be a warning to everyone that before and after events of this nature all steering/suspension/brake systems should be carefully checked.

In this case no damage was done except to Tim's bank balance and his ego. But it could have been much worse. If anyone has any other constructive ideas about what might have caused the crash, I am sure Tim would be very interested.