flash1034

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Flash

TripleM

I havent tried
but I m gonna order a set of 245/35 front too for street driving. Likely to be Mich PS2
The width differentials in stock specs, ie 235 n 305 seems bit too much, inducing alot of rear end grip at the expense of the front end ( despite the car comes std either with MPSC or PCorsa )...
So I think the real easy solution is to put 245 and it should sit nicely on 8.5J rim.

prysma997gt3

Hey Stephan,

please take a look at this thread "Having fun with it!!!!! ;-)", dated 8/28/07. I have all the info there. And thanks for the compliments and the help with the wheels.

mdrums, I'm going with the flow and will get the C14s, 9 and 12s. Still going back and forth about Hoosiers or slicks.

Regards

Luiz

lawjdc

It looks like the 245/35's might be a good upgrade, but they are not N spec. Some real world observations re handling at the limit might be helpful.

TripleM

Agreed, they are not N-spec. Only the 235 is.

Having said that, people put non N-spec tires on fast cars like BMW M6 and it's perfectly safe so I personall won't bother that much.

lawjdc

I agree - but, I have the perception that N spec tires are "dumbed-down", especially the 235's, and it may not be good to mix N specs with non-N specs on the same car.

Nordschleife

ABS systems DO adjust to different tyre sizes, I frequently change rim and tyre sizes switching between summer, shoulder and winter season tyres. The ABS copes with this.

Incidentally, the ABS system is developed by Bosch, and tested by Porsche.

I have contacts in the companies that make and develop ESP/ABS systems and the project managers at the major automobile companies. Most of the time the car makers are stabbing in the dark when it comes to brakes. For example, nearly all those manufacturers who select 8 piston calipers are wasting their own money and costing their customers higher running costs, for no performance benefits, yes, you actually get better braking performance from 6 piston callipers than you do from 8 piston callipers, AND they are cheaper to buy and cheaper to buy replacement pads for. I demonstrate to the project manager of a company very closely related to PAG why his beautiful rotors were better employed as boat anchors, I won't embarrass him as he has dumped that design after being prodded for several years.

The ABS measures the rotation rate of all four wheels concurrently. Its also smart enough to figure out when I am taking avoiding action and will try and assist me and makes an effort to understand what kind of surface I m driving on, all with mixed success.

R+C

mdrums

What do you mean by "dumbed down"? Seems the load rating is what Porsche is after and I find that the N spec fronts have a lower load rating than non N spec, especially the 245's.

Is there ANY proof that the tire company's change the ingrediants in the rubber compoud for the N spec tires?

What really makes N spec better for Porsche cars than non N spec...they all have the same speed rating and if the load rating is higher than non N spec it seems to me non N specs would be stronger.

lawjdc

I don't think the speed rating or the load rating is the issue. The N spec tires are simply different than the non-N spec tires. Here's a previous thread provided by Damon at the Tire Rack.

https://rennlist.com/forums/wheel-and-tire-forum/329233-michelin-pilot-sport-cup-a-study-in-standard-model-and-porsche-n-spec.html

If you will search other threads in the competition forum, you will find that drivers who have tried both types believe that the non-N spec tires are much, much better on the track, which would seem logical given that they appear to have a smaller portion of the tire face devoted to rain channels.

Thats all I meant by "dumbed down".

brucegre

Hey Flash, it's on a 996, but I've run the 255/40 front with the 295/30 Sport Cups with no problem, and right now I'm running the BFG R1s, 245/40 and 285/30 (only sizes available), again with no problem, if you don't consider that the car is now a usable drift king a problem ...

I've run a ton of different combinations, and never had a problem with the ABS.

The cars do benefit from more front tire, no question.

mdrums

lawjdc, thaks for the reply...I was not mad about the dumbed down coment I just did not know what you were refering to. I agree too.