Can you put 245/35 front and 295/30 back?
Or do you have to go with 265/35 and 305/30, which seems to be the more popular setup?

Is it a safety issue? Weight of the car being so heavy.
Maximum weight the smaller tires(245/35 and 295/30) can handle is 1565lb front and 1874lb back. Maximum weight for the larger (265/35, 305/30) are 1819lbs front 1984lbs back.
Or is it a performance issue?

BMW alpina comes stock with 245/35 and 295/30. And the specs are similar to PanTurbo.

 

I would definitely recommend going with the 255/35/21 and 295/30/21. We have also run a 265/35/21 and 305/35/21. You definitely want to have the properly load rated tire for that vehicle. There may still be Yokohama's available, but the Michelin's are also available.

 

Guy - what does a set of 21" monoblocks run for the PTT? Do you sell them direct or do I have to go through a dealer?

 

I sent you a PM

 

If you need help with a set, let us know!