Triumph Repair: overdirve for my spitfire, triumph spitfire 1500, driveshaft

Question
Hi Jim,
I own a 1975 Triumph spitfire 1500 and I was wondering if it is possible to add overdrive to it and what I would have to do to make it happen.  I live in Boston Ma. and I was hoping you can give me some guidance as to what I have to do and how I go about it.

Thank you in advance

David

Answer
David,

It's a fairly simple install to fit an overdrive trans.

First off, you'll need to get an transmission with an overdrive fitted already.  Since you have a single rail transmission, you'd look for a later single rail with J-type o/d fitted.

The mainshafts are different, so you can't just bolt up an o/d unit to your existing transmission.

You'll need the proper driveshaft from the o/d car, or you'll need to have your driveshaft shortened so it'll fit.

You'll need a wiring harness extension for the o/d trans.

Lastly, make sure that wherever you source your trans it also includes the shift lever as they're not available new and darn hard to find used.



Cheers,


Jim