Triumph Repair: spitfire mk4 1300 gearbox, clutch disc, spitfire 1500

Question
hello
I need to change my gearbox. Is there any gerabox from another spitfire model that fits? or with some minor adjustements?
thanks
carlos

Answer
Carlos,

You can (in theory) fit any year Spitfire or Herald gearbox into you car, with all the correct pieces.  

For you the easiest is to find another three rail 4 synchro gearbox, either from a Mk IV or an early US 1500 (1973/1974).

An earlier 3 rail 3 synchro box (Spitfire MK I-III) will fit but you may have to change the flange on the front of the driveshaft as the bolt circle is different on the output flange of the transmission.

You can also fit a single rail gearbox from the 1975-1980 Spitfire 1500/ MG Midget 1500.  You'll need the driveshaft from the later Spitfire (or get your driveshaft modified) and you'll need a special clutch disc designed for the Mk IV with 20 splines instead of the stock Mk IV 10 spline disc.

Cheers,

Jim