R500 k final drive information request

[Colin_T]

Could someone confirm for me what final drive / rear differential ratio R500 k series is meant to have fitted please. 
 

Stevecarter website says 3.92 but I am being told conflicting information ?? 
 

thanks in advance 

[Jonathan Kay]

I don't know.

But you can count it by jacking at least one rear wheel up and turning it by hand and counting turns at the wheel and the prop shaft.

Jonathan

[SLR No.77]

As far as I’m aware they were all 3.62 final drive ratio c/w the 6sp Caterham gearbox, same as the other 6sp installs of the time. Only race cars had the 3.92 FD, although I might be proved wrong ….

[Richard Price]

2 hours ago, SLR No.77 said:

As far as I’m aware they were all 3.62 final drive ratio c/w the 6sp Caterham gearbox, same as the other 6sp installs of the time. Only race cars had the 3.92 FD, although I might be proved wrong ….

I'm pretty sure the period sales brochures quoted 3.92 final drive, as the original R500 max revs was over 9k (over 1000rpm more than the SLR), even though the max revs was later reduced to less than 9k rpm. On the original 22" ACB10's, 8600rpm would still equate to a theoretical more than 140mph (where a 3.62 diff would have been over 10mph greater, but it would have taken more than the quoted 235bhp to get there.....)