My newbie experience with NSX wheel sizes and TSC

Joined
30 November 2011
Messages
13
Location
Kuala Lumpur
Hi All,

A newbie here from Kuala Lumpur. Finally took the plunge 3 weeks ago and bought a '91 Auto model with 02 facelift.

Car came with a 275/35/19 R and 225/40/18 F. As the tires were about 6 years old, hard and noisy, decided to change new tires to 265/30/19 R and maintain front size of 225/40/18.

After changeout done (at a tire dealer), as car rolls out for test drive prior alignment, the TSC started blinking and couldn't get any power from the engine (for some reason, I could not override the TSC despite pressing the button repeatedly). Thought I had electrical/fuse or ECU problems (...basically panicked)
I cooled down, sat in the dealers office and remembered that the OEM size were 225/50/16 R and 205/50/15 F. Then checked an online tire calculator for diameter ratio of Front to Back.

The original front:back diameter ratio is about 0.928
My new tires were 0.993 (almost 1)

Managed to convince dealer to change back rear tires to the old one just to confirm that it was the diameter ratio difference thats causing the TSC activation (..which he agreed after I told I'll pay for the new tires as it was considered "used" and he could not send it back).

Much to my relief, the TSC did not come on after changing back to the previous wheel size of 275/35/19. So i had to buy 2 more new tires for the rear.

A happy ending of sorts is that

1) the dealer managed to sell the 'used' 265/30/19 to someone else albeit at a slightly lower price than I bought.

2) My TSC is working (though my override button is questionable)

3) I've learned something about wheel size ratio for the 91 NSX.
(The original F:R ratio is about 0.928. Does anyone know the tolerance
it has before TSC is activated?

This is an awesome forum for NSXers. I know I should try refer a bit from here before but now I really know that.

cheers,
 
For the tcs to work correctly, you have to run a larger diameter tire in the rear. If you are running the 15/16,16/17,17/18,18/19 the rear tire should have a 5% aspect ratio decrease in the rear compared to the front. Also your tire stagger should be from 30 to 50mm. If you are running the same size wheels front and rear, the tire aspect ratio needs to be the same. you will let the increased width of the rear tire increase the side wall height.

for example, say you were running 17/17 with 215/40/17 and 255/40/17( stock 02+sizes) the fronts would have (215 x .4 = 86mm) side wall height. the rear would be (255 x .4 = 102mm) sidewall height. These sizes give the rear tire a slightly diameter compared to the front, so when driving straight with no wheels spin, the front tires will always be spinning faster than the front. When you spin the rear tires the rears will be spinning faster than the fronts which will then engage the tcs.
 
Car came with a 275/35/19 R and 225/40/18 F. As the tires were about 6 years old, hard and noisy, decided to change new tires to 265/30/19 R and maintain front size of 225/40/18.

The proper size tires for the NSX in 18/19 are
rear: 275/30/19 or 265/30/19 (as you correctly attempted to try)
front: 215/35/18

The 225/40/18 you currently have is both too wide and way too tall.

My suggestion would have been to keep the 265/30/19 and buy yourself a matching front set of 215/35/18.
 
Last edited:
tbnsxt, Hapa88, N Spec,

The front wheels do rub at full turn with my current wheels set up. The rear seems fine.
In fact, now I'm aware that my front inner wheel arch covers/ are missing. (Either removed or possibly shredded from previous).

Anyway, now I've decided to get a fresh set of 17/18 wheels with 215/40/17 F and 265/35/18 R after luckily meeting up with Mr. nsxinkl here in KL recently, who have spare sets of Advan Model 5's.

Will just keep the 18/19 wheels (Lowenhart LD 1's, I think) as spare for now.

Hope i can feel improvement in acceleration with these smaller and lighter sizes when I put them in.......can't wait

thanks for your comments, guys
 
You would also have a great improvement if you only chose the correct tire sizes - for your '91:

215/35/18

275/30/19
 
tbnsxt, Hapa88, N Spec,

The front wheels do rub at full turn with my current wheels set up. The rear seems fine.
In fact, now I'm aware that my front inner wheel arch covers/ are missing. (Either removed or possibly shredded from previous).

Anyway, now I've decided to get a fresh set of 17/18 wheels with 215/40/17 F and 265/35/18 R after luckily meeting up with Mr. nsxinkl here in KL recently, who have spare sets of Advan Model 5's.

Will just keep the 18/19 wheels (Lowenhart LD 1's, I think) as spare for now.

Hope i can feel improvement in acceleration with these smaller and lighter sizes when I put them in.......can't wait

thanks for your comments, guys

Mr. nsxinkl here did you a huge favor. Advan Model 5's are beautiful on the NSX and are relatively light. LD-1's are heavy as hell and belong on a 4 door sedan. You will notice a big difference.
 
Just sharing my Before/After pictures for the change out done from Lowenhart LD1 18/19s' to Advan Mod 5 17/18s'.

Though (to my mind , at least), the chrome Lowenharts 18/19 has its attraction visually by filling up the wheel arch and being shiny, its heavy.

With the 17/18 Advan 5,

1. it looks sportier
2. steering is lighter
3. acceleration is improved
4. bumps and potholes (....%#! KL city roads) feels less jarring and smoother due to lighter unsprung weight.

I'm happy with the change.

(hope I've attached the pictures right. Guy in blue is nsxinkl )
 

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the advans look great!

the lowenharts (i dont think the styling is in any way suitable for nsx looked hideous IMHO)

anymore photos of your car? your car looks badda$$

you car now needs a slightly lower drop and more updated side skirts (oem 2002+/GT-ONE/stacys..)

attachment.php
 
whoever puts these hooptie ass wheels on nsx's should be slapped IMO.

I think your new wheel choice is excelent for looks and performance!

love the yellow btw. I think the 02+ sideskirts would be a great choice to finish off your 02+ conversion.
 
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