As above guys really..

I have a 2" lift all round, 350D rear end running 10" fourtrax rear wheels and 350D rear wheels on the front end to give an equal (ish) width.

So.. What are the biggest (tallest) tyres I can run without a major loss of power?
I was thinking stick with 25’s until I source the parts to reduce the gearing?

All suggestions and thoughts appreciated

EDIT: it’s a 4×4!