Just took my stock 16's off my 85, put the 90 style 17's on. I could not tell much of a ride difference between the 2 sets.......... 

I purchased my '84 C4 from the Mecum auction in Kissimmee, Fl in January. It came with Goodyear Eagles that were over 10 years old. Even though the tread was good, I didn't dare drive on highways for fear of a blowout, so I got 16" Falcons for the original rims. Very inexpensive through Discount Tires Direct (dot com) compared to what local dealers including Discount Tires wanted.

Having said that, last month I decided I wanted spiffier rims, but couldn't find any 16" rims that I liked, so I moved up to 17" (Verde Regency rims.) I had to also move up to 17" tires, so I ordered 4 Falcons again, and again from Discount Tires Direct. A bit more but still very affordable compared to what I expected for Corvette tires.

My ride was harsh last spring, so I also ordered "Easy Ride" transverse rear spring and replaced the original. I also put on relatively inexpensive Monroe gas shocks. The combination of Falcon tires with the suspension changes makes the car very civilized. I don't note any difference between the 16" Falcons on the old rims and the 17" Falcons on the new.

I do want to sell the 16" tires and preferably the rims. I've driven about 500 miles on them since they were installed and then removed. I've had one discussion already with a potential buyer on the Corvette Forum, C4 threads, but nothing firm yet. Pictures: https://plus.google.com/photos/112396878582813304182/albums/5936441386979202417?authkey=CJDh0fTqme38_wE

 Changed my mind. Had the wheels powdercoated Matt Black. It looks meaner now with the red rotors an calipers.

Looks good.