C'mon Harv.
Sorry, got distracted by work
.
Haven't seen the grey crashie modified this way before - most of the mods I've seen have been replacements (with adaptor plates) for other boxes, for example:
a) Riley 2.5. It had a 4-speed manual overdriven transmission with the following ratios (the respective grey motor crashbox values are in brackets):
1st gear 12.93:1 (2.99:1)
2nd gear 8.03:1 (1.59:1)
3rd gear 5.6:1, or 4.11:1 in overdrive (1:1)
4th gear 3.9:1, or 2.87:1 in overdrive
Reverse 17.52:1 (2.99:1)
Even with the change in diff ratio (the Riley had 4.1:1 compared to the old grey motor at 3.89:1), this is a pretty torque-oriented gearbox. I assume that bolting one to a grey would have been for hillclimbers rather than those chasing top-speed.
b) BMC B-series. This is probably not the three-speed crashbox fitted to the Wolseley 24/80/Austin Freeway, but likely the four-speed all-synchro offered on the Marina. The Marina gearing is shown below (the respective grey motor crashbox values are in brackets):
1st gear 3.412:1 (2.99:1)
2nd gear 2.12:1 (1.59:1)
3rd gear 1.43:1 (1:1)
4th gear 1:1
Reverse 3.753:1 (2.99:1)
Note that the Marina box has the same top-end capability, but is lower geared in 1st gear.
c) Datsun 1600. The Datsun gearbox was either a four-speed manual (the F4W63L and F4W63L gearboxes) or five-speed manual (the FS5W60L and FS5W63A gearboxes). I’m assuming most people were chasing the five-speed manual, which had a top gear ratio of some 0.85:1 compared to the grey motor crashbox at 1:1.
d) Jag.
Cheers,
Harv