johnlee

After reading the threads here, I went to tirerack.com to buy new tires to replace the Pirelli PZero Assimetricos (noisy, harsh ride) on my C4S. To my dismay, none of the tires frequently recommended here are available in the sizes I need (225-18-40F, 295-18-30R) The Goodyear Eagle F1 GSD3 does not make 295-18-30. Michelin PS2 does, but does not make 225-18-40, except as an XL or extra load variant. IS THIS OK? . Tirerack offers the Michelin PS Rib (older design?), Continental ContiSportContact2, and Bridgestone S-02A,and of course the Pirelli PZero which I currently have and don't like. I don't want to make major sacrifices in performance, but I would like a smoother, quieter ride as it is my daily driver. I don't track (yet). I would greatly appreciate some guidance.

John
2002 C4S Lapis Blue/Metropol Blue (with new PSE)
2006 Mercedes-Benz CLS 500
2004 Infiniti QX56

Rams86

Try Contiental Sport Cont's....I think they a re god tire

bert smith

The PS2 in a 225/40/18 isnt N rated, but as long as you are ok with that the extra load version will work just fine. Porsche frowns upon non N rated tires, but I am not even going to open that can of worms. The ps2 is your best choice for a tire though

johnlee

What ARE extra load tires? Or rather, who are they made for? What are the downsides (ride, road noise, performance).

SPR

ps2 235 is N rated

bert smith

An extra load tire has a reinforced sidewall to accomidate the weight of a vehicle. For example, a 225/40/18 will fit a Honda Civic, yet that car has nowhere near the weight of a porsche c4s, that is where a tire designed for extra load comes into play.

johnlee

Thanks for your replies. Are you aware of any meaningful downsides to extra load tires. I want to replace the PZeros as they are noisy and ride harsh. The PS2 are suppose to be much better in this regard, but I'm wondering if the same will hold true for extra load tires.

arenared

My guess is that the XL rated tires would be a hair stiffer, but you might be able to back off on the high rear pressures needed by 911s a few PSI. 235s in front is another option. My ContiSports were by FAR the worst tire I've ever had. Also, seriously consider the Yoko Advan Neova which looks to be a bitchin' street tire (used on Lotus Elise).

http://www.tirerack.com/survey/Surve...VAN+Neova+AD07

teflon_jones

I'd give Tire Rack a call to get a definitive answer on the XL tires and whether they're appropriate for your car.

Chaos

Car and Driver this month rates them all Conti Sport Contact 2 seems a good choice !

johnlee

Again, thanks for the thoughts. Much appreciated. I saw the Car and Driver article, and although the Conti's placed 2nd, the narrative wasn't very flattering. Basically, the Conti's placed 2nd based on the strength of their performance under wet conditions. and I live in Las Vegas.

Tirerack says sure you can use the extra load tires but the handling, steering, and ride may be a little worse compared with the regular (non extra load) tires...didn't inspire confidence.

Are the Potenza S-02A still well-regarded here?

ebaker

I put N rated 235/315 PS2's on my stock turbo wheels. They are great. They should fit the C4S also. PS1's or Pilot sport ribs should be good also. I previously had Rossos and they were much more comfortable than asimetricoes. They are not as sticky as PS2's thogh.

Palting

I have the PS2 225/18/40 XL on the front of my C4S, and the PS2 N2 in the rear. That combo has already seen several days of track duty.

If you do mostly street, the the PS2 XL is fine. The whole PS2 combo you get will ride quieter and more comfortably than your original PZero's.

If you track your car relatively frequently, and run stock suspension and stock settings, stay away from the PS2's. They were designed with somewhat softer sidewalls, a fact you can readily appreciate by squashing the sidewall in your grip and comparing them to other tires like the PZero or the Rib. This was meant to allow the tire to flatten the shoulders and give you a wider contact patch on heavy cornering. Good idea, bad execution. The shoulders can't take it, and I've worn the shoulder itself down to the cord in only a few days at the track.

You can also put 285/30-18's in the rear with out any appreciable change in performance or looks. That opens up some more choices for you. I did that when I looked for R-compounds for the track.

I've heard but have not confirmed that 235/40-18 with stock/turbo rims in the front for the 4S specifically causes rubbing issues.

I know the PZero Assims have a harsh ride and are noisy. BUT, the have a heck of a dry grip that is hard to beat for a street tire, and the shoulders are thick enough for heavy track use. I use them for combined street and track duty, for when I have to drive a long way to the track or am too lazy to change into my track wheels.

Eric - Plug Guy

I had four sets of PZ's on my '99 C2Cab. Could not believe the difference when I put PS2's on there for the final set. Sold car.

Then the 04 C4S Cab came with PS2's - very thankful. PZ's suck. Just no reason to have 'em unless they are the only tire around. Yeah, plenty of grip, but too damn noisy.

johnlee

Palting,

I see you have a C4S. It's apparent you went through the same issues. I really appreciate your comments...definitely helpful.

With regard to your comment about the shoulders wearing out...it makes me wonder whether this is the reason 225/18/40 tires come only in XL (extra load). Otherwise I can't see the logic in offering 225/18/40 XL but not 225/18/40. After all, it's not a particularly unusual size.

John