hey have an 09 TT thinking of switching my setup to an off road style.

I wanted to know what is the smallest sized wheel I can fit with my calib and best off road tires.

Havent been on in a while

Thanks in advance!

 

From what I have learned, the MY09 CTT is when they switched to the Brembo 380mm brakes as standard. So if that is true, the smallest diameter wheel is 19" to clear your brake calipers.

Best off road tires is subjective and you will not find many people here with specific mud / all terrain tires. You are better off doing your own specific tire research for the tire size needed. Or checking another forum where they do more offroading - like the Range Rover forum.

 

Gee, my '05 takes 18" and I am using General Grabber AT2's. These are wider and more durable than the Pirelli's Porsche recommends.

 

I thought of going to the 32" diameter tires Porsche used in the Transsyberia race but haven't heard yet about whether the PCM settings can be re-programmed for the larger diameter tires.

 

Your speedo would be slightly off. This shows going from the stock 18" size to the 265/65/18

(2 notes. First if you set the computer for the factory 275/45/20 tires this ratio would be closer and your speedo may only be 2-3mph off. Secondly the 265/65/18 is less than half an inch larger than what we all run when running 285/35/22)

 

My snow tires are worn down to the wear bars so I'm debating new snow rubber in the larger size or just going to an All Terrain tire into the larger size.

 

 

I went to Costco; they hesitate to put 265x65x18's on my car because of the potential to rub the wheel wells and all.

Do the larger tires rub in any of the settings the stardard Turbo air system has?

 

No idea.

 

I have an '04 CTT with 265/55-20 Nitto Terra Grapplers.
20x8.5 +48mm wheels.

I also have the 18's but never cared to mount anything to them.

I have no issues other than the low speed rating. They handle relatively well for what they are. Quiet and comfortable and just enough aggressiveness to get you through what the Cayenne can handle. Obviously they are no street performance tire but they help bring out the CTT's other ego.
Sidewalls are decent and they can absorb a fair amount of slow speed impact while off-roading... mild to maybe moderate. (but my idea of off-roading may be extreme to most.)
Took a trip through the Ozarks and they handled the twisty pavement rather well, to my surprise.

Been a serious off-roader for 20 years building Jeeps, buggies etc. You will never be able to run a true off-road tire without a lot of issues on the cayenne. i.e. Interco Super Swampers. Plus, I would never have the need to put my CTT were an old beater Jeep should be.

Check out the Treg forums. Those guys seem to utilize their rigs for the dirt more than us.

Not the best pic but it gives you an idea. I can take a better one if you would like?

 

I've also built many jeeps and other Offroad rigs in the 37"+ size .


Have any pictures of the whole CTT with those tires on it?

 

You must mean the 265/50R20 since they don't make a 55 of that tire

http://m.nittotire.com/tires/terragrappler/specs?wd=20

Also, that tire measures up shorter than the 265/65r18 they ran on the Transsyberia rigs. Would still love to see a picture of the CTT with them on it!

 

Nothing but that low res avatar.

I will get some posted probably this weekend. Daylight is short these days and work is long.

 

Ooops! Double tap on the 5. yes they are 50 series.

 

Thanks. Look forward to it!

Btw....a 285/50R20 could be a nice set up for an aggressive look and a fat looking tire!