MK3 GTi Gearbox in MK1 :)

Could you spare a moment helping a guy from Norway?

I have just completed an engine switch in my MK1, and now i want to switch to a more modern MK3 5 speed gearbox (i can get hold of one which was recently serviced and rebuilt) and new mk3 GTi clutch and i was wondering what would have to be done to make the transplant? Is it just bolt on? If the flanges on the new gearbox differ from my old ones, is it possible to switch them over?

There are two reasons for why i want to make the change, starting with the first: Im worried my old 70hp MK1 Gearbox will break soon since it has a much torqier and powerful engine
And two: This is my everyday car so it would be nice to have a bit lower mileage as a result of getting a 5th gear

I know my English isnt very good , so sorry for any bad spelling or bad grammar

Any advice and help would be greatly appreciated!  :wink:

I found out that the MK3 gearbox uses 100mm splines and if i were to change them, i would have to get a MK2 gearbox that has 90mm splines... If i got a mk2 gearbox it would be stupid not to use that instead of the mk3 one

Its not as simple as "Mk3 gearbox" or "Mk2 gearbox".

First of all, you've done an engine conversion - which engine do you now have?

I have a 2E Lump in my car w. the 2E clutch and flywheel I thought it would be a pretty straight job but as you say, i have to find a gearbox with 90mm splines and an input shaft that works with my clutch (22mm?)... I thought the mk2 have some gearboxes that matches these specs? Or am i totally wrong? I havent done a lot of work on the 020 gearboxes before so i hope ill learn a bit

You can use the list on the left to find a gearbox that matches your requirements. If needs be, you can convert to 100mm inner CVJs but you'd need appropriate driveshafts, eg from later cabby or Mk2 Scirocco. If you convert from 4 speed to 5 speed, you'll also need the gear linkage including a bracket on the steering rack.

Will the gear linkage from MK2 fit the MK1? Thx for the info

nope!

Darn it! So ill have to find 5 speed gear linkage from a mk1 then.... Hmmm. I wonder what to do... Im longing for a 5th gear to get better fuel economy and a little better top speed

a suggestion is a mk2 driver box and a mk2 gti 8v clutch n flywheel , is what i'm building but leaving 90mm flanges for now

i used a 8v mk3 gti g/box with my 2 ltr conversion as i found the 23 (or thereabouts) mph per 1000 revs really helped on the motorway, the 100mm cups were easily swapped for 90mm ones although they were very tight.

abfmk1 said

i used a 8v mk3 gti g/box with my 2 ltr conversion as i found the 23 (or thereabouts) mph per 1000 revs really helped on the motorway, the 100mm cups were easily swapped for 90mm ones although they were very tight.

Seconded See here

You`ll need to resolve the flywheel clutch plate issues also by using the flywheel from the Mk 3 and I used a stronger clutch - simply do a search for more info