Porsche N-Spec Tires
#167
I agree, great post. As a corporation, Porsche should be OCD... but man we all know who else is OCD, but for reasons derived from something less corporate, more family.
#172
Benjamin Choi likes to run with fat tires. Fine. It is his choice. Since he put them on, a loss of control due to aquaplaning is his problem and he can't find PAG responsible. Does his car have better handling in the dry? Probably - not that Porsche cares, they are off the hook for any handling defect.
Jury - please allow me a correction. When it comes to dry handling on smooth pavement, nothing beats a big fat race slick. Of course it would be deadly in the rain but racers have spare wheels and rain tires for the purpose. Porsche has to assume that the majority of owners will drive their car in all weather conditions. The average guy cannot pull in for a 1 minute pit stop and fit rain specific tires after all. This forces them to compromise on tire width and tread patterns to have something which performs respectably under all conditions. Within those constraints, they come up with an intelligent compromise, then test it extensively under varied conditions. The result is the N spec tire.
Jury - please allow me a correction. When it comes to dry handling on smooth pavement, nothing beats a big fat race slick. Of course it would be deadly in the rain but racers have spare wheels and rain tires for the purpose. Porsche has to assume that the majority of owners will drive their car in all weather conditions. The average guy cannot pull in for a 1 minute pit stop and fit rain specific tires after all. This forces them to compromise on tire width and tread patterns to have something which performs respectably under all conditions. Within those constraints, they come up with an intelligent compromise, then test it extensively under varied conditions. The result is the N spec tire.
However, there are also many subjective aspects of handling. Skidpad grip does not tell the whole story. What about the balance of the car toward under/oversteer and the way the car reacts to driver inputs of throttle, brakes and steering at this point? The NSX, or Lotus Elise is a wonderfully balanced car and they have achieved this without the need of fat tires. In fact, wide tires would be detrimental to throttle induced oversteer, because those cars are lacking in the torque dept, as is the 911 when compared to a Viper of Vette, where wide tires are the order of the day.
I hope this puts the matter to rest. benjamin and jury, please watch for a PM from me.
P.S. Excellent post.
Last edited by jury_ca; 04-18-2008 at 05:12 AM.
#173
Jury, the reason I'm confused by your reasoning is because Porsche themselves increased tire width of the car from the 265s on the 3.4 996 to the 285s on the 3.6 996 and the 295s on the 3.6 996 C4S. Clearly, the increased tire width in the rear offered some advantages for Porsche to change, right?
#174
Jury, the reason I'm confused by your reasoning is because Porsche themselves increased tire width of the car from the 265s on the 3.4 996 to the 285s on the 3.6 996 and the 295s on the 3.6 996 C4S. Clearly, the increased tire width in the rear offered some advantages for Porsche to change, right?
Cheers,
#175
As the power went up, so did the rear tire width. This extra traction at the back helps tame oversteer. If the car understeers (skinny front tires, wide rear tires), then you just need to hit the brakes to get traction up front again. Fewer lawyers for Porsche to deal with.
Cheers,
Cheers,
Oh, but the dynamic balance is out of flux capacitor! Nooooos!
#176
As for your flux capacitor comment....well....stow it before Bob sees you stirring the pot again.
#177
Comment about Bob... I don't plan on staying on Bob's bad side (not that I really really care like I care about World Cup soccer or anything like that).
#178
As the power went up, so did the rear tire width. This extra traction at the back helps tame oversteer. If the car understeers (skinny front tires, wide rear tires), then you just need to hit the brakes to get traction up front again. Fewer lawyers for Porsche to deal with.
Cheers,
Cheers,
#179
My point is, even with the same level of power, Porsche makes it available with the wider tread which brings me back to my original point all along... all of this is hairsplitting so long as you're not running bike tires or running 16" rears or KYJelly-spec tires, you're fine. Enjoy the drive.
Just imagine the many others on Rennlist who run non-PS2 tires, but are perfectly happy with the performance of their 911 on their local runs to the grocery store or to the mountain valleys. Oh the horror.
Just imagine the many others on Rennlist who run non-PS2 tires, but are perfectly happy with the performance of their 911 on their local runs to the grocery store or to the mountain valleys. Oh the horror.
#180
Jury, the reason I'm confused by your reasoning is because Porsche themselves increased tire width of the car from the 265s on the 3.4 996 to the 285s on the 3.6 996 and the 295s on the 3.6 996 C4S. Clearly, the increased tire width in the rear offered some advantages for Porsche to change, right?
Are there any cases of Porsche offering wider rear tires alone as an option on the SAME car?