Time for new tires - let the debate begin - 986 Forum - The Community for Porsche Boxster & Cayman Owners

mjw930 · 12-30-2005, 02:13 PM

I most certainly would not go with the Nero's, they are an all season tire and will greatly detract from the precision as well as ultimate grip the Boxster has.

In the 18" size I'm a fan of the Michelin Pilot Sport N1 (Rib) tire. It's very quiet, has great traction, retains the proper sidewall stiffness to keep the steering from going numb and offers pretty good wear relative to the other N-Spec tires out there. In an N-Spec tire this is the most responsive I've tried.

If I was going away from N-Spec I would seriously check out the new Yokohama ADVAN Neova AD07. This tire has been getting rave reviews. The Bridgestone S-03 is also a top notch tire but it's noisier and even shorter lived than the N1 Pilot Sports.

I personally do not like the Michelin PS2's in the 18" size and have them taken off the car after 1000 miles because they simply didn't feel right. They caused the car to feel sluggish and made it tail happy at the limit, especially when off weighted in turns. Please note, this is the non N-Spec PS2 in the 225/40x18 and 265/35x18 size. The N-Spec PS2's don't seem to exhibit this trait but they don't make them in our sizes.

Adam · 12-30-2005, 03:45 PM

I'm in the same boat as well(03 with 15k miles) and I don't know if I should go with the Advans or the PS2's. Excuse my ignorance but what is N-spec and why don't they make 265/225 PS2's in N-spec form?

mjw930 · 12-30-2005, 04:45 PM

N-Spec refers to tires that have been tested and certified by Porsche. This is more than a rubber stamp (regardless of what some people on these forums will have you believe), Porsche actively tests the tires as well as analyzing the specification to make sure they meet the engineer's requirements.

In application the "N" is followed by a number. That number increments if the manufacturer updates the tires or introduces a new tire line in that particular size. 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. That means is you have N0's on the front you can't put N1's on the rear. You should also never mix brands as the N1's from one manufacturer have no relation to N1's of another.

The major advantage in using N-Spec tires is to ensure that your car is performing within the limits it was designed to. Using non N-Spec tires isn't a problem but it can introduce handling and ride issues that your dealer (if the car is still under warranty) cannot resolve.

On the flip side, there are many Non N-Spec tires that people have used on their Porsche's with great success, Bridgestone S-03's are a case in point.

As to why there are no N-Spec PS2's in our sizes, I think that's primarily because by the time Michelin had the PS2's certified by Porsche our sizes were no longer a size that any current Porsche uses. I believe the tire makers only go through the specification process when there is an expectation (or contract) that they will be used a OEM. PS2's in our sizes will probably never be OEM so it's unlikely we will ever see an N-Spec PS2 in the 225/40x18 and 265/35x18 sizes.

BTW, many here have used the PS2's and love them. Many seem to be in the 17" size but some have also used them in the 18's as well. I tried the 18's and hated them but YMMV.

I didn't like them because their high slip angles cause the front to be numb and the rear to be twitchy. They also tramline very bad compared to the PS Rib (N1). On the plus side, the highway ride was excellent up to 90 mph where the soft sidewalls reared their ugly head and made the car wander a bit. Not something I like at 110

Adam · 12-30-2005, 04:55 PM

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 · 12-30-2005, 05:19 PM

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 · 12-30-2005, 06:39 PM

Quote:

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 · 12-30-2005, 06:33 PM

Quote:

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.