TRANSMISSION
All models came with the three-rail four-speed gearbox. Deluxes came with standard ratios — OK, but not much fun so the box to go for is the V4 GT or 2000E’s close-ratio item, funnily enough known in old Ford circles as the 2000E box, even though it was also fitted to the Mk2 Lotus Cortina, and EscortTwin Cam and Mexico.You could transplant the 2000E’s gears into your existing casing, but it’ll be easier and cheaper just to source a complete gearbox and swap the tailshaft over to suit your car’s remote gearchange. 2000Es also came with a larger 8 inch diameter clutch plate, so if your base is a Deluxe (7.5-inch clutch), then any engine tuning should be accompanied by an E clutch, too.
Gearbox swaps? The much-stronger Type E (aka Pinto) four-speed will fit with some transmission tunnel work (and mods to the gearbox crossmember and prop), as will the favoured Type-9 five-speed. Both should be essential for most performance engine swaps as the three-rail is really only good for up to 120-130 bhp.The later gearboxes will also mean a switch to cable clutch operation (quite easy), or some bracket-making and a Mini clutch slave cylinder allows you to retain the hydraulic set-up. Corsairs came with either the 3.9 or 3.7:1-ratio crownwheel and pinions — both are a good compromise between acceleration and cruising. It’s an English axle under there, so you’ve got ratios from 3.54:1 through to 4.44 at your disposal from the Ford range. All can be fitted with a limited-slip diff if required.