MK 11 OVERDRIVE

[kennyd]

Who is the best person to advise on overdrives, ie required parts etc?

[iggy]

overdriverepairs.co.uk in sheffield will give you advice and sell parts accoding to there web site,

[daver clasper]

Overdrive Spares, Rugby. Dave Twigger is very helpfull.

Dave

[Guppy916]

These guys are the bees knee's

http://www.odspares.com

[kennyd]

Thanks for the replies, I should have mentioned that the car currently does not have overdrive, but I am  sure I will get the advice I need from the info provided! thanks again!

[Llessur]

If you want to change an existing non-OD car to OD then you'd be better off sourcing a complete OD box as it's easier than adding an OD unit to an existing box. Then you'll need the longer gearbox cross-member mounts, correct gearstick with OD switch (or you could wire a switch elsewhere), relay (required for the A-type OD, not strictly necessary with the J-type but it doesn't hurt to fit one anyway) and wiring harness (or make your own).

Plus, you might want to do the clutch whilst you're in there so you'd need a clutch kit, release bearing, slipper pads, spigot bearing, reinforced fork pin, new clevis pin for the clutch slave cylinder piston and preferably new bushes for the clutch cross shaft . You'll most likely need a new gearbox mount and you might as well polybush the gearbox cross member whilst it's off.

Save yourself some headaches and get the good stuff from Chris Witor (btw who also recommends a 7/8" clutch slave cylinder is used with all aftermarket clutch kits due to its longer travel over the 1" cylinder).

It's a good project if you're planning on doing it yourself. I got half way through writing mine up but my plans changed before I could finish the job and fit the new box. The link's here: https://triumph2500blog.wordpress.com/2018/04/ - as the Haynes guys say, refitting is the reverse of removal.