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I am in the process of building an R32 GTR rally car, which will primarily do tarmac. However we are blessed with some great gravel sprints around the region of NZ I am in, so going to do a few gravel events too. Now as gravel tyres only come in 15" (and I have about 100 of them left over from my old Legacy rallycar), does anyone have any idea on what sort of offset is needed in a 15" rim to fit over the factory non-Brembo R32 GTR brakes?

Will be getting some of these:

http://www.palmside.co.nz/product_pcid_15667.html

Which I know fit over Subaru 4 pot brakes, so should fit GTR brakes fine. But just need an idea on if anyone has done it and if they have had any issues regarding offset etc.

And yes, I know ATTESA isn't good on gravel. I will be running the car as a RWD for this reason and the fact that I need to learn to drive a RWD before I get soft and use 4WD to make up for my lack of driving skill! (This is also helped by the fact that I got the car with no front axles and a 25DET box in it).

Vivian

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  • 2 weeks later...

My thinking is that R32 GTR's came out with 16in rims for a reason and that would be brake clearance. Not sure if offset will help around the problem. Sorry for playing the devils advocate but you might struggle to get it to work.

Good luck and post up some pics of it power sliding on gravel :)

Or just run 16's

http://www.demon-tweeks.co.uk/motorsport/competition-tyres/maxsport-rb3-tyre

mate of mine got a set of these for his GTS-t and worked pretty well on the gravel roads in cardwell forest.

Only catch was they there ordered as mediums and were like marshmallow soft.

Does anyone else make a 16" gravel tyre, ie any of the big brands? I haven't seen anything but mud and snows so far. However of course the advantage is with 16s I can get wider tyres too I guess. And of course rims are easier to come by too.

Also you make a good point, I will look and see if I can find an aftermarket brake calliper that fits better than factory!

Bridgestone used to sell a 16" rally tyre - don't know if they still do. They don't regularly import them to Oz, but if you can get hold of a friendly Bridgestone dealer they may be able to find out for you.

There was a whole stack of brand new bridgestone rally tyres being sold cheap on ebay a couple of years ago, after a failed attempt to make Bridgestone the ARC preferred supplier (or something like that). Brand new tyres were being sold off at huge discounts, including 16"

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