Anybody running 10.5's on the rear

LUV2REV · 13 July 2003

Just curious to know how many Guy's are running 10.5" wheels on the rear of the NSX ? I am having Kinesis K57/58's built for my NSX right now and it was suggested that I run 10.5's on the rear by Kinesis. No reason other than to get the biggest footprint as possible on the road. The wheels are 17x8's up front and 18x10.5's on the rear. I will be putting Kuhmo MX tires on the car as well. Anyone have any experience with the MX's ? I will post pictures in 4-6 weeks when I get the wheels.

Veleno · 13 July 2003

There are some NSXs using 17x8.5 fronts and 18x10.5 rears, so yes it can work depending on the offset.

I'm sure Ken will chime in here soon to give you more info regarding contact patch and its misconceptions.

Is there any reason for running the Kumho tire?

Dali Racing carries Falken tires in sizes 225/35/17 and 285/30/18, the best proportioned looking tire size for 17/18" wheels IMO.

Be sure to post some pictures of your car/wheels when you've mounted them on.

Ponyboy · 13 July 2003

I'm running 18x10.5 wheels with no problems.

nsxtasy · 13 July 2003

Sheesh. A wheel manufacturer who doesn't know what they're talking about. The width of the wheel and tire have nothing to do with the size of the contact patch that the tire puts down; it only affects its shape.

I would decide which size tires you want to use first, and then decide on the best wheel width. For example, most folks with 17" front and 18" rear wheels are using 215/40-17 front and either 255/35-18 or 265/35-18 rear. That will prevent rubbing and won't hurt performance as much as the larger sizes mentioned above for the Falkens.

The Kumho Ecsta MX tires come in the 215/40-17 size for the front and the 265/35-18 size for the rear (but not either of the oversize sizes Richard mentioned for the Falkens), so these are the sizes I would recommend using. According to the specs for the MX, the 265/35-18 size can fit onto rims with widths of 9.0 to 10.5 inches, but the specs for that size apply to the 9.5 inch width. If I were buying wheels and planned to use these tires, I would not use more than 10 inches for the width. I think the wheel manufacturer is giving you very bad advice, since they obviously have no idea what size tires fit an NSX best.

LUV2REV · 14 July 2003

A bit of misconception on my part, sorry, the guys at Kinesis did not indicate a larger "contact" patch with 10.5's. That was my notion. The wheels they have built for NSX's in the past are virtually all 10.5's on the rear, so came the recommendation. Obviously the difference between a 10 & 10.5" wheel is nominal. They will just fill out the rear wells about right. ( In my eyes anyway ) The guy's at Kinesis are experts and know what they are talking about ( If you watch any endurance racing the big 3 for wheel supply on both factory backed teams and privateers are Fikse, Kinesis and BBS. The reason for Kumhos are the MX's have had favorable reviews from people in Calgary ( mostly Porsche and BMW drivers ) They are very sticky, wear reasonably well and are fairly cheap. They give up a bit of wet weather traction for dry grip of course. You pay big bucks for the S03's wet weather abilities. ( It is also a great performance tire ) I have never had the urge to take my car out when it's pouring rain anyway. If I get stuck in the wet, I play it safe.

Ponyboy · 14 July 2003

Sheesh. A wheel manufacturer who doesn't know what they're talking about. The width of the wheel and tire have nothing to do with the size of the contact patch that the tire puts down; it only affects its shape.

Once I get my S03's from the Tire Rack early August (supposed to ship July 25th) I plan on doing a contact patch test comparing the stock rear 225's with aftermarket 285's. I'll post results and pics.

theWB · 14 July 2003

well ......i have hre 841 18x8 and 19x11 ........ no ptoblems...im putting on my brakes so ill post my pictures..also put s0-3....225/35/18 and 285/30/19 ........

nsxtasy · 14 July 2003

Ponyboy said:
Once I get my S03's from the Tire Rack early August (supposed to ship July 25th) I plan on doing a contact patch test comparing the stock rear 225's with aftermarket 285's. I'll post results and pics.

The Tire Rack has conducted similar tests in the past, and found that the difference in the size of the contact patches was less than their measurement error (which was around 1 or 2 percent).

Ponyboy · 14 July 2003

Yes, I remember us discussing that one.

I'm curious to see what the difference and how much wider and/or bigger the contact patch w/ the bigger tire will be.

nsxtasy · 14 July 2003

I'm not sure but I think they had a glass plate that they drove the car's tires onto, and measured the surface area from underneath...

Ponyboy · 15 July 2003

That's going to be difficult test to replicate. I was thinking of applying some kind of goo to the tire and setting it down on some kind of paper or something along those lines. The glass is probably a better experiement but I'm kind limited in method.

maomaonsx · 16 July 2003

Shawn, did you ever try to fit any big brake kit under your 17x8.5 TE37s yet?

Ponyboy · 16 July 2003

Hi George,

Yeah, I tried.

Needs at least a 5mm spacer. Dali's out of stock so a 7mm is on the way. I'll post pics when it's done.

Lud · 16 July 2003

Ponyboy said:
That's going to be difficult test to replicate. I was thinking of applying some kind of goo to the tire and setting it down on some kind of paper or something along those lines. The glass is probably a better experiement but I'm kind limited in method.

Jack the car up
Rub an ink pad on the tire treads, covering an area you know is larger than the contact patch
Put a piece of paper or cardboard under each tire
Lower the car completely so all the weight is on the tires
Measure width and length of resultant tire "prints"

Set the e-brake and lower the car evenly so the tires don't roll and it should be fairly accurate, I would think. Make sure the corresponding tires from both sets are at exactly the same air pressure!

ScienceofSpeed · 17 July 2003

Here's a shot of Volk Racing TE-37 19x10.5

http://www.scienceofspeed.com/public/042403/new_rear_quarter.jpg

Cheers,
-- Chris

maomaonsx · 17 July 2003

those 19inch TE37s look so good! I wish they change the spoke design to that for the smaller size TE37s as well.

fkong777 · 17 July 2003

Chris@SoS said:
Here's a shot of Volk Racing TE-37 19x10.5

http://www.scienceofspeed.com/public/042403/new_rear_quarter.jpg

Cheers,
-- Chris

That doesn't count.. that NSX have flares.

Anybody running 10.5's on the rear

Similar threads