The 2006 GT will have the optional 18" Fans available. My question is when you increase the rim size you decrease the rear end gear ratio. The 17" Pirellis with the 3:55 rear end should be faster then the 18" BFG's which theoretically should have <3:55 rear end OR will the 2 tires Pirelli/BFG's be the same height?? If so the question is moot. Does anyone know the height of the 18" Fans with the BFG's as well as the height of the 17inchers with the Pirellis?? Thanks

 

Sorry, that yellow face was supposed to be a "less then" mathmatical sign anyway it was supposed to say "less then 3:55" . What do you all think?? :scratch:

 

The ratio doesn't change unless the tires change diameter, not the rims. 255/45/18s have the same diameter as the 235/55/17s, so there will be no change.

 

Edit it and go to "Enable emoticons?" and uncheck that. That is pretty funny thought.

As for the question I would think it wouldn't make a difference, but I'm not positive about that.

 

I just checked to be sure. The 255/45/18s are .14" smaller than the 235/55/17s (27.04" vs. 27.18" respectively). So, with that minimal of a change, there will be no effect on the rear-end ratio. Also as an aside, I don't think those BFGs on the showcar will appear on the production car. Those tires are all-out summer ultra high performace tires, and they are not approved for snow use. I figure they will go with something a little less aggressive as well as all-weather, but I could be wrong. God knows I have been plenty before.