[Andyinchville1]

Hi All,

I am adding larger tires to my MK 4 TDI Jetta wagon shortly. I mostly drive highway so the upgrade will cut RPM's at speed.

Factory size is 195 65R 15

I am currently running 205 70R 15 tires

I am looking to upgrade / upsize to 205 75R 15 OR if they'll fit 215 75R 15 tires

I am not modifying the car to accept the larger tires just adding the tires, so nothing extra to hang into the wind.

I have spoken with some folks on the other site I am a member of and they think raising my car with the larger diameter tires will kill aero and negate any effective gearing advantages. (NOTE : interestingly the steel wheels with the factory sized tires are the same weight my new Aluminum wheels with the current tires .... I'll probably pick up 2 to 3 lbs weight per tire going up to the 75 profile tires).

I cannot see how raising my car 2 inches all around (no additional rake etc ) would negatively affect aero since the car was not scraping the ground to start with. What do you think ?

on the flip side , is it possible , that raising the car can actually help aero because there would be less effect from swirling air reflecting off the ground etc... I know its only 2" or so so maybe any changes would not even be measurable?

I figured I would ask here as well since there was a section specifically for it and I think this site is much harder core into mods for fuel efficiency which is great ! (yes, I know I NEED to make my kamm back and underbody tray .... I got some ideas but now I just need to do it!).

Thanks in advance for any and all input on this.

Andrew