Time for new tires - let the debate begin

[Adam]

I'm a bit confused. Are pilot sport rib the same as standard Pilot sports? Porsche used PS1's as OEM equipment. Why not use the PS2's? I believe Porsche is still using the 265 and maybe the 225 18 sizes on the 987 and the Cayman.

[bigislandboxster]

Porsche doesn't specify a specific N number by model but they do state that you shouldn't mix N numbers on the same car

This seems a bit confusing to me.....If the N designation was approved by Porsche, what would be wrong with putting N2's with N3's? Aren't we splitting hairs a bit on this? I have N2's in the back with N3's in the front, same brand of tire Pirelli Zeros, and I have had zero problems!

Just because they say not to do it doesn't sound good enough to me, because I'm not hearing WHY this is not advised?

Don't they also say not to use any tire without the N specification, but plenty of people on this board have had great success using non N specified tires?

Sorry for the rant...but...

Call me skeptical

[mjw930]

Originally Posted by bigislandboxster

This seems a bit confusing to me.....If the N designation was approved by Porsche, what would be wrong with putting N2's with N3's? Aren't we splitting hairs a bit on this? I have N2's in the back with N3's in the front, same brand of tire Pirelli Zeros, and I have had zero problems!

Just because they say not to do it doesn't sound good enough to me, because I'm not hearing WHY this is not advised?

Don't they also say not to use any tire without the N specification, but plenty of people on this board have had great success using non N specified tires?

Sorry for the rant...but...

Call me skeptical

What's wrong with mixing N versions is that the different numbers indicate a different tire. Either the compound or construction or both have changed, hence the different number.

The Why is as simple as That's what it is stated in the manual. It didn't find it's way into the manual to take up space, it's there because the engineers know a little more than the guy at your local tire store.

As for using Non N-Spec tires, I never said that was a problem. As long as you maintain the minimum speed and load ratings of the OEM tire you won't have any safety issues and I agree, there are a lot of people using non N-Spec tires without a problem and in fact, my track tires are not N-Spec.

[mjw930]

Originally Posted by Adam

I'm a bit confused. Are pilot sport rib the same as standard Pilot sports? Porsche used PS1's as OEM equipment. Why not use the PS2's? I believe Porsche is still using the 265 and maybe the 225 18 sizes on the 987 and the Cayman.

Actually they produced 2 version of the Pilot Sport (PS1), the N0 was the older, directional tread.



The N1 has a hybrid tread, much like the MXX3 on the Pilot Sport (PS1) carcuss (sp?). The Pilot Sport Rib is what the N1 Pilots are called here in the US.



The 18" sizes on the 987 S (and Caymen S) are 235/40x18 and 265/40x18. Since they have a different rolling radius, front to rear, I suspect the PASM (PSM) system has been recalibrated to accommodate this.