Nice A40 photo!Maguire Mini wrote: Those Firestone tyres were brilliant compared to the Dunlop's available at the time, we used them in sprinting/hillclimbing in a soft compound, I think they were IB or YB11 and the circuit tyres IB or YB19, they had so much grip my brother had one push off a Mamba wheel on the front, which then dug in and the car cartwheeled into a little ball, I was waiting at the start line for my turn when an official told me he had gone off, they took me up to the wreck, which looked like a tent had been pitched on the grass, the roof up in a point, a re-shell being required.
Found another photo from the B&W set at Silverstone, not a Mini but it had got an A series.
We switched from Dunlop dry tyres to the Firestone 1B19 soon after they first appeared and like many of the Free Formula 850's achieved quicker lap times. Firestone 1B19 6.0x19.3x10 dry tyres on 6x10 Mamba alloys with Dunlop CR65 Mk11 (320) 5.00L-10 used on S reverse rims for the wet.
Our previous Dunlop drys were CR81s, in another Mk1 forum thread 'ivor badger 2' suggested:
"A bit depended on which Dunlop dry you used. IB !9s were probably better than 700 CR81s, but against 900 it was probably personal preference. 900s were probably too wide for an 850. Possibly anything was better than a CR70. Again it ended up personal preference between IB19 and Dunlop slicks or car setup."
viewtopic.php?f=5&t=17362&start=20#p142923
Found some old Dunlop info here:-
Dunlop Racing Tyres
Tyre Types
CR-65 Pattern
A tyre providing good tread stability in dry and wet conditions. Tyres in this pattern are produced in “L”, “M” and depressed crown constructions to provide the variables required by today’s racing drivers.
CR.81 Pattern
A dry pattern developed for the asymmetric 450/700-10 Mini tyre because of the potentially high rate of wear on all Minis.
Compound Types
184
This is the standard all-purpose compound for use on sports and touring categories, identified by the figures 184 stencilled on the sidewall.
236
This is a dry weather compound developed for the high rate of wear experienced with Minis. This compound is also available in sizes to suit Abarth and Alfa Romeo touring cars for use in long-distance races and is identified by the figures 236 stencilled on the sidewall.
http://www.motorsportmagazine.com/archi ... cing-tyres