Summer tires mess up handling

[the Spaeth's]

The car is now back so I could double check the tire size. The tires are
235/45/17 Bridgestone Potenza S-O3 on 17"x 8.5" Ronal R28's. I have the same
problem with running big Porsche brakes and needing the clearance. My 16"
winter tires fit just fine but there is not much clearance. I would love to
get away with just doing tires, but I really don't want to buy tires and
then have the same problem.

Thanks for the ideas.

Craig