ls911

If that's so wrong I don't want to be right

Benjamin Choi

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.

VGM911

I agree with the others.....very good post. Thanks for taking the time to write it.

dresler

what would be useful is those who have experience with non-nspecs and track, to post their impressions.

what happened to the kinder, gentler Ben?

Benjamin Choi

ls911

Hmmm...what's that guy shoveling?

Don't expect anyone to bend over even if kinder/gentler

spots on a cheetah

jury_ca

Oh, I have no doubt that by Ben adding wider rear tires he has increased the level of grip in the rear, not to mention effectively widening the rear track of the car, which also reduces the level of grip lost due to weight transfer during cornering. So if one were to measure objectively, he could very well increase dry cornering speeds.

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.



Uh-oh, I'd better head back to my corner now.

P.S. Excellent post.

nycebo

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?

AllanJ

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,

Benjamin Choi

They also upsized not just the diameter, but increased the rear wheel/tire width on the 3.6 997 Carrera.

Oh, but the dynamic balance is out of flux capacitor! Nooooos!

AllanJ

I'm only talking width. I don't care about diameter unless they need bigger wheels to fit around massive brakes.

As for your flux capacitor comment....well....stow it before Bob sees you stirring the pot again.

Benjamin Choi

I'm talking both.

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).

nycebo

Agreed. I'm aware that the extra power might have required more traction. That was my point.

Benjamin Choi

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.

jury_ca

The answer lies in your post. Going from the a 3.4 to a 3.6l also increased the amount of torque available, which gave them the ability to use wider tires in the rear. The increased grip would give the car better acceleration and with additional power, you could still induce throttle oversteer. Also in 2002 the chassis/suspension would have been retuned to take advantage of the wider tires.

Are there any cases of Porsche offering wider rear tires alone as an option on the SAME car?