Upgrading wheel sizes

[4AU4LIFE]

I have a 92(duh) manual trans currently running 16's and 17's. I recently purchased a set of wheels/tires that were 17's all the way around.
When I installed the wheels, it was very smooth with no issues. The front wheels were 8" wide with 205/40/17's. The tire wasn't wide enough for the wheel and looked very dangerous . I upgraded to a 235 and then had rubbing issues. :frown:
Also, when I changed to the larger tire size, the TCS light came on which would require me to manually turn it off each time I got into car. I didn't want to do that.
I am having a hard time finding a set of 16's-17's that I like and would consider going to 17's-18's with a lower profile tire.
My question is will I always be running into the TCS light issue if I go that drastic a change from the OEM sizes?
BTW, the rear tire was a 245/40/17.

 

[nsxtasy]

My question is will I always be running into the TCS light issue if I go that drastic a change from the OEM sizes?

Yes - which is why you shouldn't. The reason you had problems with 235 front is that the outer diameter is MUCH greater than the stock size (which is part of the reason you had severe rubbing, the greater width being the other part). With the proper tire sizes - ones whose outer diameter are close to stock - you won't have any trouble with TCS.

With 17" wheels front and rear, your best bet is to use 215/40-17 front and 255/40-17 rear. You shouldn't have any TCS problems with those sizes.

Another option is the tire sizes you were already using: 245/40-17 rear and 205/40-17 front. You can check the specs for the particular make and model tire you were using, but most 205/40-17 tires ARE approved for 17x8 wheels and it is NOT dangerous to do so. So feel free to go back to those sizes if you still have those tires.

If you go with 17" front and 18" rear, your best bet is to use 215/40-17 front and 265/35-18 rear. You shouldn't have any TCS problems with those sizes. (Get 18x9 or 18x9.5 rear wheels. If you need to get another pair of 17" front wheels, 17x7.5 is a better fit than 17x8.)

 

[4AU4LIFE]

That is the vital info I have been searching for!! I have been studying the FAQ section on wheels/tires for a few weeks now and still have been able to clearly understand what I can safely do with bothering with the TCS.
Thank you Ken.

 

[Jin1976]

What tires do you have. I normally find that 205/45/16 tires eg. Michelin PS, Bridgestone G3 and Kumho Ecsta Supra did not fully cover the lips of my 16x7.5 wheel until I got Pirelli Dragon of the same size. I found that the Pirelli 255/40/17 is as wide as the Bridgestone 265/40/17 and its nice that the outside thread is different than the inside one. The dealer said this is good for wheels that have negative camber as the inside compund is harder than the outside.

 

[4AU4LIFE]

On the fronts......225-40-16 Eagle F1
On the rears.......255-40-17 "
I have TSW Venom wheels but haven't taken them off yet to look and see what offset, or widths are. I feel like the fronts are probably 7" wide and the rears 8"-8.5" wide.
The sidewall of the tires are about 1/4 past the edge of wheel all the way around. I really like the look of it and would like to keep that look while upgrading to the bigger wheels yet again.

 

[nsxtasy]

I have TSW Venom wheels but haven't taken them off yet to look and see what offset, or widths are.

When you do, remember that the width is measured where the tire bead resides. It is NOT the outer dimension of the wheel at the lip (which is usually about an inch larger, although the difference can vary). The same thing is true of the wheel's diameter.

I found this out recently when shipping a pair of 15x6 wheels in a box with interior dimensions of 16x16x16, and found that they both just barely squeezed into the box with absolutely no room to spare in any dimension.

 

[CarCrazed4Life]

3 Combo's that have worked for me:

1) Stock wheels, stock tires: 215/45/16 & 245/40/17
2) Stock wheels, 225/45/16, 255/40/17
3) 17x8 front, 18x9.5 rear: 245/35/17, 285/30/18.

And no I do not have rubbing. We'll see how it works with the car lowered once I put them back on (new set of 17/18s though...)

Charlie.

 

[4AU4LIFE]

3 Combo's that have worked for me:

1) Stock wheels, stock tires: 215/45/16 & 245/40/17
2) Stock wheels, 225/45/16, 255/40/17
3) 17x8 front, 18x9.5 rear: 245/35/17, 285/30/18.

And no I do not have rubbing. We'll see how it works with the car lowered once I put them back on (new set of 17/18s though...)

Charlie.

That is good to know. What offsets did you run with those sizes?

 

[docjohn]

Wow 245/35/17 on the front?! I have never seen that size tire used; what brand comes in that size?Also did you use a spacer or have any fender lip rub,and is your car stock ride height?

 

[nsxtasy]

245/35-17 front tires are just about guaranteed to rub. Have you removed your plastic fender liners (and, if so, have you had many "reverse dings")? Have you "rolled" your fender lips? Otherwise, maybe you're the 1 in 100 exception...

what brand comes in that size?

The only make and model of tire that Tire Rack shows in their top two performance categories (the only categories commonly used on the NSX) is the Goodyear F1 GS-D3.

Also, keep in mind that the traction control is designed to be used with the tire sizes that were stock for that particular year NSX. Different tire sizes were used in '91-93 vs '94-01 vs '02-05. This means that tires that don't cause TCS problems for, say, a '94-01 NSX, might still cause TCS problems for an NSX of some other year.

 

[4AU4LIFE]

Yeah the TCS deal is what I'm fighting now. I would like to step up to 17'-18's but realize that is going +2 on front and rears.
In order to do that, I would have to get an ultra low profile tire to remain as close to overall stock diameter as possible. Then I'm giving up the 'ride' of the car and opening up the chances of damaging wheel if I hit a hole. Wouldn't have the tire to absorb the impact of it.

 

[CarCrazed4Life]

Offsets were 17x8 ET 42, 18x9.5 ET 37.

The 245/35/17s are the same height as the 215/40/17s at 23.8" These tires are about 1.2" wider though then 215s. I did not remove my liner, Offset seems to be the most crucial aspect here. 215/45/16 and 215/40/17s are almost the same height (23.6")

285/30/18s are 24.8" and the 245/40/17s are 24.7" TCS was not an issue with any of my setups thus far. I will most likely have to roll my fenders (which seem easier on our aluminum bodied cars) when I get suspension work done.

 

[nsxtasy]

The 245/35/17s are the same height as the 215/40/17s at 23.8"

Hmmm... that doesn't sound right. The outer diameter of the 215/40-17, calculated from the tire's dimensions, is indeed 23.8 inches. When you calculate the outer diameter of the 245/35-17, it's 25.3 inches, 6.5 percent larger.

 

[BioBanker]

Hmmm... that doesn't sound right. The outer diameter of the 215/40-17, calculated from the tire's dimensions, is indeed 23.8 inches. When you calculate the outer diameter of the 245/35-17, it's 25.3 inches, 6.5 percent larger.

This is very interesting - by my calculations, and by this LINK, it looks like a 245/35/17 is the same height as a 215/40/17.

So if that is indeed true, what is the offset for a 7.5 inch rim that will allow such a width to work up front? It worked for carcrazed on a 8 inch rim with a +42 it seems.

Anyone else run a 245 up front without having to modify the fender/liner?

 

[twizted]

I am running the following with no fender rolls, no TCS issues and 2" Drop:

17x8.5 Front - 225-35-17 Tires
18x10 Rear - 275-35-18 Tires

ADDED: And the top of the car is at the same height has the bottom of the rear-view mirror on my Dad's 2004 Caddilac Sedan :smile: LOL!

 

[RP-Motorsports]

This is very interesting - by my calculations, and by this LINK, it looks like a 245/35/17 is the same height as a 215/40/17.

So if that is indeed true, what is the offset for a 7.5 inch rim that will allow such a width to work up front? It worked for carcrazed on a 8 inch rim with a +42 it seems.

Anyone else run a 245 up front without having to modify the fender/liner?

I have NEVER heard of a 245 up front with stock fenders!

We run a 235 with a +43mm, so math would say to try a +48mm with a 245 tire. You could always start there (+48mm) and then you can add spacers up to 5mm to dial it in. A +43mm with a 245 tire, will stick out a bit, and then there is nothing you can do with spacers to dial in. It is always better to err on the + side (5mm) to be safe.

 

[NSXT]

SPA is correct, a 245/35/17 and 215/40/17 have similar diameters. But diameter is not the only thing which determines rubbing on the inner fender.

See post #13

Offset can be used to prevent such inner fender rubbing, but you can certainly go too wide and rub on the outer fender lip under compression. Although with a 245/35/17, I would be a little more concerned with the tire being moved outside the fender and rocks being slung down the side of the car.

 

[emdoller]

I am running the following with no fender rolls, no TCS issues and 2" Drop:

17x8.5 Front - 225-35-17 Tires
18x10 Rear - 275-35-18 Tires

ADDED: And the top of the car is at the same height has the bottom of the rear-view mirror on my Dad's 2004 Caddilac Sedan :smile: LOL!

Your car looks amazing!! Can you tell me what offsets you have on your wheels and exactly what you did to lower it?

Damn...

Ed