18s with TCS

[pinkhairman]

I've just fitted my NSX with 18x8.5/18x10 Advan GTs with Michelin Pilot Super Sports, 245/35r18 and 265/35r18 and my TCS is now almost always flashing when I leave it on. If anybody has experience of knowledge about tire sizes effect on the 1991 model NSX, please let me know if this is normal and to be expected.

 

[Speedmaster]

I have 18s all around and do not have TCS issues. I will go and take a look at the series of tires to get an idea. Be back later.

 

[jwmelvin]

Those sizes are way too close between front and back for TCS to be happy. Your results are expected.

 

[docjohn]

the front would have to be 215/35/18...or maybe make the rears 285/35/18

 

[pinkhairman]

So, if I changed the rears to 285s, would the TCS be happy? Also, thanks for all the help and advice, it is much appreciated!

 

[jwmelvin]

285/35-18 would be on the edge of okay. Larger would be better. Especially because as the rear wear the split will be worse. You must have wide fenders to fit that front size? For TCS, 305/35-18 would be the right size in back for those front tires. Afaik those are well into the range of wide-body fitment.

 

[clutch1]

For running the numbers, you're fronts are 2% smaller in diameter, and according to the NSX faq page (http://www.nsxprime.com/FAQ/TireWheel/wheeltech.htm) a '91 has a minimum difference of 2.7% (up to 12.7%), so you'd need something with a little more sidewall in the rear.

A 265 40 18 in the rear would make it within compliance, according to the maths.