Sidewall lip on 215/45-17 Bridgestone Turanza EL400-02 (Prius V)

Yep - I have the 17" Toyos. Was pleasantly surprised to see the convex ridge all the way around. Must be a bit of defense for alloy wheel scrub on curbs... Nice design.

 

Tideland,

Your answer would be my first guess too.

That said, I wonder if the ridge might also have an aerodynamic purpose
as well, that being to direct the air passing over the rim/tires outward
just a smidge and perhaps even bridge over the gap between the rear of
the tire and the bodywork.

Maybe a lucky Gen III owner could do some tuft testing and take pictures
to see what the OEM airflow down there looks like.

 

It has nothing to do with aerodynamics--it's to protect the wheels on low profile tires. I've had it on all my cars for the last 10+ years.

 

The Scion wheels I just bought with those tires have them "lip" it is to rotect the rims from curb damage. I know for sure the Goodyear Eagle GT also has them in that size as well.

 

Correct, and FYI my Lexus IS 350 (factory Bridgestone Turanza ER33) has it on the front 225/40 R18 but not on the rear 255/40 R18. It all depends on the tire and size, I guess.

 

Put 2 new Cooper CS4's on the Camry and Express had a set of 4 Toyo Proxes 245/45ZR17 with the rim protector in the showroom, but the 235 width didn't. My mom's Infiniti G35 Coupe has Falken Ziez 512. Front 225/40/17 with rim protector and 245/45/17 rear also with protector. It seems the higher performance tires have them.

 

My guess, based on the on the front versus rear disparity on mine and the visual appearance (225 front 255 rear, all else the same), is that it depends on the vertical distance to the base of the wheel. Whether that's unique by tire manufacturer, or a common standard, I have no idea. Start with picture comparisons at a place like Tire Rack, if the picture is clear, or call them. They usually have a good handle on their products.