30mm spacers...max tyre size ?

[Mark V8]

My Discovery has 30mm spacers fitted and I'm on the lookout for some new tyres (Poss. BF Goodrich) as the existing Pirelli Scorpions (235 70 16) are struggling with the mud....
Whats the maximum width tyre I should be able to fit to my existing rims ?
Any recommendations other than the BFGs, guys ?

[edmason]

Depends which wheels you have. If you already have spacers you are probably running with LR alloys. Aftermarket steels (8 spoke or modulars being the most popular)have more offset, so sit further out in the arches than the standard wheels. The final effect is much the same. Your insurance may not like spacers, because they tend to put all the loading onto the studs, rather than the centre boss. You won't get away with any larger tyres without trimming the rear arches, which is very straightforward on a 2 door, but a right pain with a 4 door because you have to re-build the door bottom. Bronco Grizzly Claws are good in mud, and pretty civilised on road, if noisy, and also cheap. Some people are wary of re-moulds, but if you are doing much off-roading you will damage tyres, so it seems like a good compromise to me. I currently have a set of Pro-Comps on my Disco, which are not quite as aggressive as the Grizzlys, but still pretty good. I Also have a set of Insa Turbos on black 8 spokes, which are pretty uncompromising on the road, but superb in mud, but they did chew the bodywork before I trimmed it! I might sell these if you were interested. I can send pics if you e-mail me. Can't seem to get them to upload here.