Originally Posted by Thrush
The wheels themselves (both three and four spoke) are universal items - only the bosses are different. They have the same 8 hole bolt on boss style that you see on Momo wheels etc...
The 6 bolt fixing has a different PCD to the momo etc steering wheels.
Originally Posted by Thrush
The three spoke rims DID come in two different thcknesses, and were options from the Ford RS Options catalogue. These were availabel for the S1 and the 3dr Sierra (bosses), and later when the Saff Cos came along and the S2, Ford carried on the wheels and updated the bosses accordingly (for hornpush bosses)
Bosses were also available for mk3 Fiesta's swell - other marques aswell possibly, but I only know of the mk3+4 Escort, mk1+2 Sierra and Mk3 Fiesta for 100% definite (I have had a boss for a Mk3 Escort (4spoke wheel), bought a 3spoke that came fitted with a boss for a mk3 Fiesta, and my mate had a 4spoke on a S2 with hornpush boss, and have seen pics of both Mk1 and Mk2 Sierra's wearing them with Ford bosses)
There was also an earlier version of the wheels that fixed to the boss via 6 countersunk M5 bolts, as opposed to the usual M6 - a friend of mine had one on his Mk1 Escort (genuine wheel and boss). Bosses were also available for Mk2 Escorts, Capris (same spline as the Mk1 Escort, but longer shroud), earlier Fiestas - probably also Cortinas and Granadas, but I've never seen one.