[Aladdin Sane]

Doesn't appear to be too many tire options, like none, in the OEM size (235/40/20) besides the stock Conti 5Ps. Anyone running something different that isn't summer high performance on these rims (black OEM 20s)? Other sizes work in real life?

 

[caug]

https://tiresize.com/calculator/
the difference is minimum.
you can use any kind of tires summer or winter.
performance and not performance.

 

[Wayne]

Go just a little wider and you have many more options. IMHO Michelin MPSS are the best. They are introducing the next generation in March.

I pre-purchased the last (current) generation MPSS rears for my 997 since the fronts last 2 times longer. I'll install those in a couple months and then both axles should wear out together.

My point is that I recommend using the same tire on all four corners ... do not mix.

 

[Aladdin Sane]

Thanks. It's always fun getting new tires. I've run the Michelin AS Pilot Sport variants on a couple vehicles and liked them a lot. The new AS 3 version is here and I will definitely look at that one.

 

[NoDozeJoe]

Thanks OP! I was looking or options as well!

 

[NoDozeJoe]

Go just a little wider and you have many more options.

So what size would you suggest that has the least variation from the OEM? (tire newbie here)

Thanks in advance.

 

[Wayne]

I've got my data at home, so I may revise this later tonight ... but as an example from a quick trip to the Tire Rack website -

The OEM (and only tire of this size ... we waited 2 days in Barcelona to have one shipped to us after a slash and grab event) is the Continental with 27.4 inch diameter. With this value when the tires are new the speedometer reads exactly to the GPS speedometer on Waze. In other words the diameter is a bit big since DOT requires that the speedometer read 2 mph over actual speed (in a straight line the Waze value is basically exact).

Michelin makes a Pilot Super Sport that is 245/35ZR20 with a diameter of 26.8 making this (27.4 - 26.8)/.274 % smaller. That's 2.2% and will put the speedometer 1.1 mph higher at 50 mph.

The wheel width will accommodate the extra 10 mm.

The sidewall height will be 3.375 inches instead of 3.7 inches (a loss of 10%) and this may create a stiffer ride (welcome in my opinion).

You can also go to 245/40 and have a bunch of options (including MPSS) and keep the taller sidewall. But now your speedometer is reading low and you may be collecting speeding tickets.

Personally I'm against going skinnier.

I'll check my notes in the History Book I've put together for the 45 and if it is different I will let you know later tonight.

 

[NoDozeJoe]

Thank you for the reply Wayne. We all appreciate your data and input.

 

[Wayne]

Just to confirm ... The information I posted earlier was correct (MPSS 245/35ZR20). I took a picture of my notes from my GLA book, but every time I try to post it my phone crashes.

 

[NoDozeJoe]

The information I posted earlier was correct (MPSS 245/35ZR20).

Last question, promise. Will the extra width make the tire rub at full turn L and R? Thanks again!

 

[caug]

no rub

 

[reety82]

Tires

I too am looking for tire options. I just bought a 45 and will be looking at 30k miles per year on the car. From what I have read, I'm not expecting the OEM tires to last and they are quite pricey to replace. 245/40R20 is about 3/8" wider and 3/8" larger in diameter. Speedometer changes are minimal at less than 1 mph up to 65 mph (which is as far as the online calculator took it to). I want to see if anyone has run this tire size. I want to confirm it fits on the OEM 20" wheel and no issues with rub on the suspension system or wheel wells when making sharp turns.

Thanks,

 

[NoDozeJoe]

I run 245/40ZR-20 BF GOODRICH G-FORCE COMP-2 A/S XL (UTQG 400 AA A) since the beginning of the year (2017). So far so good, no rub.

Here's a thread I started asking for the proper tire inflation rate (37psi) which includes photos of the tires installed on my car:
http://www.glaowners.com/forum/merc.../20113-proper-tire-inflation-245-40-20-a.html

 

[Audi Junkie]

The Comp-2 AS are awesome. Michelin owns BFG.