Ive been dabbling with the tire calculators and such trying to find the best tire size form my brand new Enkei RPF1 9.5 +15 all around wheels. Ive got an eye on the Potenza RE960AS Pole Position in size 245/40/18 all around. Would this work ok? I also have the option of going with 245/40/18 fronts and 275/40/18 rear. Which would be better? I want an aggressive look that wont sacrifice traction. Thanks!

 

Personally, I'd go with a staggered setup. The Z naturally oversteers a bit. An inch or two wider in the rear is the way to go. Also, 245 on the front would probably be fine, but anything bigger and you'll notice the car "walking" side to side at highway speeds.

 

 

Yeah +1 for 275's rear. Will plant the back better/provide better balance and give a better look.

 

thanks for the help.

 

It actually understeers and bigger than 245 doesn't make the car walk from side to side. Please don't help when you don't know.

275/35 275/40
245/40 245/45
245/40 275/40
255/40 275/40

are all great combo's you can run with your wheels.

 

The Z does not naturally oversteer.
What tire combination do you suggest to fulfill your 2" wider in the rear statement? I have 265s on the front, and it tracks (walks) just fine.

 

ok awesome. Ive noticed most all season tires only have 245/40/18 and 275/40/18 and nothing in between. I think Ill keep looking since These potenzas didnt get very good reviews from Z owners.

 

I think Kevingalls is referring to the bump-steer you get on some expressways when driving wide tires on the front. I noticed this driving with front 275’s on I-80 (this expressway has more trucks than cars, and the trucks cause significant “ditching”). 275’s on the front in this case wander significantly, while 245’s track very well.

This isn’t a problem at lower speed (even on irregular roadways) or smooth roadways at higher speeds.

--Spike

 

also. Will 245/40/18 and 275/40/18 on 9.5 all around affect my very near future install of stance coils. Will I be able to lower the car a good 1"/1.5" front/rear.

 

Not at all, but why do you want your car to sit front high like a prerunner ?

You can also get bump steer/wandering from to much camber, incorrect offset (yes anything other that +30 is incorrect ) and of course the crowned roadways. We have that bad here in Vegas, just about anything without the track of a fullsize truck will wander on our surface streets. Oh ya , graded concrete will also cause this.

 

haha my typo. 1.5"/ 1" respectively. No way in hell do I want front high. Thats just an initial drop too, it will drop more after a little settling.

 

Just measure it out and do an even drop. It sits pretty level, make sure when you make your adjustments its done with a full tank.

 

good point.

 

i have 255/35/19 up front and 285/35/19 out back
never had this walking thing you guys are talking about.
maybe the roads in florida are a bit better

 

What are your wheel offsets? 245 on a 9.5 will have a little poke to it.

 

they are all +15

 

255's on the front won't wander.

Front 275'sw will wander on some roadways (I described this situation earlier in the thread).

--Spike