EDIT:
Wheel info: 18x8.5 5-4.5/120



I bought an '03 350Z Touring 6 months ago and just discovered I need new tires. The previous owner put on a set of Enkei 18" wheels. One thing is odd however, the tire sizing he went with:

Front: 245/35/18
Rear: 245/45/18

I'm not sure why it's setup this way but I'm guessing it's for clearance... since all 4 wheels are the same width (which is different than stock, right?).

What would happen if I go 245/40/18 for front and rear? Seems to be more cost effective and I found a decent deal on a set of tires on Craigslist. I guess clearance in the front is the only concern. I don't think the previous owner did anything to the suspension however (although I'm not positive, it just looks that way).

How do I know if it will fit?

 

Welcome. There is one important fact that you are not telling me. How wide are the wheels?

 

If you are not rubbing with the current set-up, I see no reason why you would rub with what you've proposed. However, I would suggest even wider tires since they'll fit, just let us know the wheel width and offset that are stamped on the inside of the Enkeis.

SS

 

Excellent, I'll check tonight when I get home. I rode the motorcycle to work since the tires are shockingly bad. Which, actually... brings me to another topic, perhaps for another thread. All four tires have gone bald on the inside 3" of the tread. There's still TONS of tread left on the rest of the tire. I am guessing the previous owner set it up that way for cornering?

BTW, is there any way to infer the wheel width from the tire size currently on the wheel (e.g., 245). I am guessing they are 8.0", but I will have to check.

 

He went with a 245/45/18 in the rear for better support and more rubber on the road. At high speeds you do not want anything super low profile ie a 245/30 or lower. It will suck.

But to answer your question, yes a 245/40/18 will fit. Frankly I would leave it as 245/45 but thats just me.

Or stagger it. Get 17s for the front and 18s in the rear.


Edit - and to answer the reply above this one, it was either cambered to hell and done improperly, or you need a god damn alignment bad.

 

There is no way to tell wheel width from tire width. Wheel width may be stamped on the inside of the wheel. If not check with a ruler.

 

Additional Information
Location:
Portland


And this information is important. Are you driving a 350Z with or without VDC?

 

It has VDC... and I always drive with it enabled.

 

Then once you get the wheel size figured out, you will want to study this: https://my350z.com/forum/wheels-and-tires/203755-will-these-tires-work-with-my-vdc-enabled-car-read-here.html.

 

Ok, here's the size info for all 4 wheels:

18x8.5 5-4.5/120

 

Recommended tires for a 8.5 inch wheel are 245 plus or minus 10 mm. For suggestions see: http://www.350zmotoring.com/modules....ex&name=Wheels.

 

Does that mean 245/40/18 will fit fine on all 4 wheels?

Will it screw with my VDC traction control?

 

Bueller? Bueller?

I guess the thread got moved from the main thread and now it's silent.

 

I have 245/40/18 on the front they fit fine on 18 x 8.5

 

Front and back? After reading the VDC thread I'm worried about screwing up the ratio by putting the same size tires on the front and rear.

 

Just do 245/40 front and 245/45 rears

 

I'm a little thrown off by the wheel sizing? Shouldn't it be 5-4.5/114.3?

Anyways, 245/40/18s are fine. Im running 255/40/18 up front on a 9.5" wide wheel and 275/40/18 in the back on 10.5" wide. Offsets are pretty low, too, +15. At one point, I also thought about getting the same size all around, but just stagger the tires bc it's going to be more of a pain worrying about rotating/treadwear, TPMS if you have to, not to mention overall looks filling out the wheel wells, etc.. Just my $0.02. You're really not saving THAT much $$ by getting the same size all around.

 

I agree: 245/40/18 will be fine with the 8.5".

 

Ok... One last question...

What if I went with:

Front: 245/40/18
Rear: 245/45/18

Will that size delta screw up the traction control?

I just discovered that my (cheap) options are much more broad with 245/40 vs. 245/35, so I am thinking of ultimately putting "40" profiles on the front and keeping the same "45" profile on the rear.

What do you think?

 

I have 06 stockys with 245/40/18 F and 275/40/18 R Kumho Ecsta MXs dropped about.. 2inches without fender roll. no rub until hard cornering and no rub going over speed bumps but rears are very close to rub.
you should go wider back.
more grip, meaner look.