cjc357

Hey guys just bought my 08 g37s. Last owner just put new tires on her. Goodyear Eagles all season tires. While I would really rather have performance tires I think I have a bigger issue

He used 245/40R19's all around instead of the 225/45's in the front

What impact do you think this will have on the cars computers and/or performance/handling?

Thanks!

Jamler

Actually, with the 19"... When upgrading you should have 245/40's on the front...
Most go with 275/35 in the rear, but 245/40 is the stock size on the rear.

So actually, I don't think you have an issue at all... Don't get smart and try to rotate
them though... Your rear wheel is 9" wide where the front it 8.5"

Enjoy

cjc357

So going with the same tire size on two different width rims is ok?

I assumes having the smaller/narrower tires on the front gave better cornering or something.

I had no idea the rim sizes were different. What if who ever changed the tires did not know this either and they are mixed up, say one on the front left one on rear right. How can I check this?

cjc357

I just read the manual, I guess there is a pin or something that prevents the rear wheels from being installed on the front hubs. So that answers that question.

So I guess that leaves me with So going with the same tire size on two different width rims is ok?

Again the noob question would be what is the benefit of the different tire size from front to rear. Am I missing out on anything?

hispeed-lowdrag

iTrader: (7)

Isn't it crazy how reading the manual can answer so many questions?

By having different tires on the front and rear you can keep the sidewalls the same, thus giving you the same total width of all 4 tires. Since the rears are wider than the fronts, you get a wider tire so that the narrower tires that go on the front dont have to be stretched (lowering the sidewall) to fit the rear

Jamler

Hispeed explained the reason for bigger in rear... But you're really OK with
your current setup... Should not hurt you. In fact, since the tire size is the
same all the way around... You can actually rotate your tires. So, although
for handling it is optimum to have slightly narrower front tire, you're fine and
may actually get longer wear from your tires with the opportunity to rotate.

There are a lot of good documented threads on here about tires, wheels,
spacers... And all the crazy variations... Good Luck

I'm new to the G as well... having just got mine too...

Neal@tirerack

iTrader: (2)

That size is perfectly fine. Common upgrade that won't cause any issues.

SM_Shadowman

Yeah, but you'd have to take them off the wheels and have them remounted & balanced every time you rotated them. Probably would cost less in the long run to just let them wear out earlier.

cjc357

That you guys for all the help. I guess this is the stock brand of tires for these cars. I know this question is VERY subjective but would you guys think that good quality "summer" performance tires would be a big difference in handling, ect over stock.

Is it worth it to upgrade to better tires and sell these b/c they only have maybe a few 100 miles on them.

SM_Shadowman

I found a huge difference with the stock summer potenzas on my 2009 6mt sport sedan, and the a/s eagles on the loaner car I got from the dealership a few months ago. Maybe the Eagles were just more worn, but I felt a lot more slipping when I tried to accelerate fast -- definitely less grip.

The sport model in factory condition has the sport wheels and summer performance tires -- using A/S tires seems like a downgrade or at best a compromise. Slightly a waste of the sport package I suppose.

But depending on where you live, you may have to also get winter tires. I skipped that this year because I just bought the car and didn't want to spend more money right away and it was a huge mistake in hindsight. This fall I plan to buy some blizzaks mounted on cheap 18" rims and switch them out.

cjc357

Thanks. I will not be using the car in the winter so I will start looking into some tires. Now just to figure out what size I want to get!

beerme986

iTrader: (2)

this is a performance car, dont ruin it with all season tires. dedicated summer and winter wheels are ideal and will make the car drive like it should