1971
The Competition History of RAD 366G - Marcos 1600GT :1968-1974
Over the winter break, I decided to press on with my racing life and to further this I would now take the Marcos to meetings on a trailer and cease to use it as a road car. This would allow me to modify the car much more.
The following description covers the second of a set of major modifications carried out by Stan Gray and Tony at Trowbridge. I have taken the following work from his bill of 10th April 1971, with the engineering having been done during the winter before.
- Remove engine and gearbox. Fit close ratio gears (Rocket box). New bushes on front suspension. Rose joints on Panhard rod with strengthened bracket. Balance conn rods and crankshaft.
- Machine 0.150 " from block and piston crowns
- 1 set Powermax pistons
- 1 clutch Assy
- 1 set inlet and exhaust valves
- 1 set valve springs
- A6 camshaft
- Competition distributor
- 8 push rods
- 1 set main and big end bearings
- 1 set close ratio gears, selectors, layshaft etc
- 1 crankshaft + tuftriding
- 4 Lotus conn rods
- 8 cam followers
- 2 Rose joints
- clutch components
Tyres:
At the start of the year, we used 5.25 M 13 -970 and set these on steel wheels widened to 7”; New set purchased 8th May 1971.
One wheel failed at Thruxton on 6th June 1971 (No.140).
On 10.7.71, I bought 4 x 175/550 13 type 350 racing tyres at Gloucester and race records show that these were used on 24th July 1971 (No.118) at Castle Combe with 7" Minilites. Records also show that I ordered 4 x 7" Minilites from Tech Del, date unknown.
Races:
Date | Circuit | Club | Practice | Race | Finish | No |
April 12 | Castle Combe | BRSCC | 1.18.8 | 13.27.1 (10l) | OK. | 108 |
| Our first outing of the year with a personal fastest lap yet of 1.18.8 Photo 13 | ||||||
April 25 | Thruxton | BARC | 1.38.8 | ? (10l) | 10/22 (C4) | 86 |
| Another personal fastest lap 1.38 in race. Pulling 7000 down Brooklands. Plugs misfiring. NGK. Photo 14. | ||||||
May 2 | Thruxton | BARC | 1.44.4 | 12.0.8 (7l) | 12/17 (C3) | 131 |
| Race combined with GT cars. Chevrons etc. Spun at Campbell. Photos 15,16. | ||||||
May 15 | Castle Combe | BARC International | 1.25.1 | ? (7l) FL 1.19.9 | 4/5 | 109 |
| The setting was for a F5000 race which was entertaining. We were in a supporting race with 5 entries. Had a push start and came last. | ||||||
May 23 | Brands Hatch | BARC | 1.11.4 | 10.33 (10l) FL 1.0.0 | 12/17 (C5) | 119 |
| Wet practice on a damp track. Was quicker in the race. Very narrow track and hard to overtake. Dull. Photo 17 | ||||||
May 31 | Castle Combe | HDLCC | High Speed Trial | 18.44.4 (14l) FL 1.18.3 | Qualified | 9 |
| A nice outing with the Hagley. I was required to complete 14 laps in 20 minutes to qualify. My time was 18.44.4. Another personal quickest of 1.18.3. Photo 18. | ||||||
June 6 | Thruxton | JDC | 1.39.2 | Dnf FL 1.37.8 | Dnf | 140 |
| Misfiring at Brooklands in practice but new plugs (N62C) for race saw a personal best time in the race of 1.37.8. Disaster soon followed when the n/f wheel detached itself from the car at Seagrave on lap 9. Plate sheared. Scary. Photos 19 – 22. | ||||||
July 24 | Castle Combe | BRSCC | 1.17.2 | 13.08 (10l) | 7/18 (C3) | 118 |
| New plugs AG901R from Autolite. New tyres 175/550-350 CR 65 MK 111. 7200 into Quarry. What a difference. Personal best time 1.17.2 in race | ||||||
Aug 14 | Silverstone GP Circuit | BRSCC | 1.55.4 | ? | 17/25 (C7) | 26 |
| Modsports was combined with GT cars. Practice was in wet conditions and I used the L tyres. We had damp conditions for the race and I changed for my regulars. I thoroughly enjoyed racing on the Grand Prix circuit. Woodcote at speed is quite something. Photo 23. | ||||||
Aug 29 | Thruxton | BARC 100kms | 1.37.2 | Dnf | Dnf | 168 |
| As it turned out, this would be my last race of the year We had a decent practice time of 1.37.2 (PB) but in the race we were in collision with Mike Westminster on lap 12 and we both retired. I cannot now remember a thing about it. | ||||||
Summary:
An interesting year of ten races with considerable improvement in our times. Castle Combe 1.17.2 (85.80mph) and Thruxton 1.37.2 (87.26mph). I am also learning more about race craft.
© Ian Gemmell 2024