...claim performance upgrades by adding wheels and tires.

I'm a member of a couple other MB related forums to get car specific information and I get a real kick out of performance upgrades that involve the "installation" of a certain drop in high flow racing air filter - most of us know to whom I refer and these guys have just dropped $40 to $70K depending on their country of origin on these cars and don't even understand that they could very well dust the block. Add to that you start talking injectors and chips and other such diesel specific platform free (or typical across the platform) upgrades and you just get deer in the headlights.

"Man, I just those decals on the rear tail fin aren't really worth 5 HP after all?"

Sorry, I just get a kick out of it.

 

Most wheel changes are for looks. Some do increase performance by reducing sidewall flex and/or increasing the contact patch. But it comes at the price of a harder ride and more road noise.

On my own car, I upgraded to 15" wheels because the larger front brakes required the clearance.

 

i don't know much about cars, but i did work at a tire shop for years and some of them steel wheels weigh a ton. so i could prolly see the benifits(?) of tire and wheel upgrades, but i do agree, i see alot of my brother in laws freinds and there cars and i know where you are coming from. they add stickers and wheels and cool lights. maybe a wing or two, (which i think prolly add more weight then they do good). oh and i can't forget about the paint job, man that paint job has to be great. the car could have a million miles and barely running anymore, but the paint, oh man the paint looks great on it. i am always telling my brother to put more money into motor, trans, rears, and such. not just looks. i always tell him, it sure looks good sitting in the driveway.