5th gear ratio mod

[R0B]

Do you have a link for a 6 speed box conversion? i keep reading the different boxes need different clutches etc, being new im not across a;; the 1.9 variants and there differences

[R0B]

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[JTop]

I'll answer simply and quickly
Yes. Boxes of the same generation, O2r(Seat Cupra R+others), O2s(Polo +others), O2m(older Audi S3-TT couple others) and will match up to the block no issue. The box codes all vary. (I'm forgetful so I may have mixed these up)
BUT. Their mounting method to the Polo chassis will have to be varied to accommodate. Ie. box is cut up to suit the gearbox mounting bracket. Then you too have to focus on the driveshaft hub cup sizes, as they will vary from box to box and to the car you are putting it into. SO do your research before you dive into a box.

And as you do go with a different box. They will have their own input spline of varying counts.
So you do need to update the clutch disk and optimally; full kit to suit this change.

Hope this gives you some idea. Enjoy