17's would probably ruin the handling of the car after all it was designed to run on 14's, I've found with big rims they tram line horribly even with the camber and castor correctly set which makes for a nasty drive. These cars are real drivers cars and I think it's a shame to put overly big wheels on and drop them so low they become a lesser car to drive.
My opinion though and if it's what you want go for it.
Nick