After a couple weeks with my 2005 5AT, I can tell you they got the suspension right. The sport package with the 19's and stock Potenza RE050A tires plant the car nicely.
I am running the tires at 41psi and it seems a good setting.
At high speed (above 80mph) the car is VERY stable.
The car goes through twisties very easily and very flat.
The manual shift mode on the 5AT is actually quite good, it shifts fast.
The exhaust sounds great, this car is fun!
Overall, a lot of performance for the money.

 

Hey I got the same car as you except I have aero. You run the tires at 41 psi? Im running them at 35psi the suggested psi. Whats the difference?

 

at 41 psi, better fuel econ., at 35 better handling. u decide. BTW stick with 35psi, its smarter IMO.

 

Not really a question of which psi is "smarter", but rather your driving priorities. At 35 you get WORSE handling, you are getting too much sidewall flex in the twisties. Of course tires too hard will break loose easier.
I tried a lot of psi settings, currently using 41 because I found it a good compromise.
If you are not into cornering, 35 will give you a softer ride, but if that is your priority don't get the sport suspension.

 

So 35 isn't a good mix with the sport suspension? If so why do they recommend 35 then?

 

One reason 35 is the reccommended PSI is the tires wear relatively evenly then.

If you run 41, the center of the tire will wear out faster than the sides.

The higher pressure should change the shape of the contact patch, making it more long and narrow. This means that instead of spreading the contact across 3/3 of the tire, only 1/3 (the center third) of the tread is being used. This may mean that you wear out your tires 2-3 times as fast...

I hope you like buying tires. They are only $1062 at the Tire Rack.

Then again, I could be wrong...

 

I myself will stick with the 35 psi recod.

 

Saw the rims today on a brand new white coupe, and I like them better than from the pictures. I wish they had made them a little wider or something. Too bad they had to take Pilot Sports out, my biggest gripe about the Z is it didn't get them. Going to have to invest in some SO-3's soon for my Z.

 

Who said 35 is not a good mix with the sport suspension? Infiniti, as most manufacturers do, usually recommend a tire pressure that will yield a comfortable ride for most people.

 

Your concept is valid, but the tire wear figures you pulled out of your hat are not. In the last 23 years of driving with tires inflated above the figure on the door jamb, not once have I experienced the center of the tire wearing out faster than the sides.
Why? Because the difference between recommended (compromise) psi and what I run, in this case 6 psi, is not enough to cause the EXTREME wear scenario you described.

 

Just wondering why the technical guys aren't jumping into this. I swore that I always learned that lower PSI gave better performance, just like more negative camber... It doesn't make your tires wear evenly.. But it yielded greater performance benefits.

 

It depends what kind of performance we are talking about. Straight line drag racing - lower psi is better for off the line grip.
When I am spending a day driving on curvy mountain roads, a little extra psi gives a crisper turn in. Of course too much air is not good - easier to induce wheel hop in rear and loss of grip in front.
I like to experiment with different psi and will adjust according to the kind of driving I plan on doing.
Mon-Fri to/from work I might run lower psi than I do when running through the mountains/desert in San Diego/Riverside/San Bernardino counties.

 

Well too lower is just as bad a too high. Infiniti's sug. of 35 is the happy medium.

As for 35PSI being bad on the supension, BS! Bouncing over inflation is worse!

 

if you can't decide which psi is better, than pick somewhere inbetween

do like 38 psi lol