We'll be running the 235/85 Mud Terrains, which you'll probably say is a bit big
Mmmm, I am free to change my mind though! Just getting my excuses in early!
Seriously I am beginning to think about the benefits of the larger tyre - however at the moment I am playing to the strengths of my car, which is on the fast gravel stuff so lower profile and less side wall flex makes more sense.
30 sounds sensible - but play it by ear because the ground is always hard at Driffield and for most of the course grip will not be an issue. On Mike's Scottish moorlands there is often a benefit to dropping the tyre pressures.
For example on the muddy stage of the Hillrally last year we toyed with the idea of dropping the pressures and then wacking them back up for the forest sections.
Cheers
H