deepbluejh

4/32" difference side to side would be annoying up front and dangerous in back (potentially damaging your differential).

commander-data

Thanks for all the replies. I have ordered a new matching tire. It should be here tomorrow.

s2kreeper

Your math is correct there, but you're not looking at the correct piece that matters. You need to analyze the difference in one rotation of a tire compared to the other.

Assuming your rolling radius, one rotation on a tire is: 2pi(11.5) = 72.26"
Adding that .125 to the 11.5 gives: 2pi(11.625) = 73.04".

While it might be small, lets look at the difference traveled for say... 10 miles for an avg commute (10mi is out of my ass, but it sounds easy for maths).

1 mi = 63360in * 10 = 633600
73.04/72.26 = 1.01
633600 * 1.01 = 639936
639936 - 633600 = 6336/12 = 528' of difference JUST 10 miles. More driving, more shredding.

1% may not seem like a lot, but because tires rotate so many times, it adds up really really fast, especially across the life of a diff.

Awesome! Glad you're getting it fixed.

commander-data

One more thing. My right rear was replace because it got damaged in an accident that I described here with photos. The wheel was not directly hit but suffered cosmetic damage from debris (pieces of front bumber, license plate, license plate frame mounting hardware, etc.) from the other car. I got brand new OEM wheel and tire put on and 4-wheel alignment done. When I got the car back, I noticed that the new tire had 40PSI while all the other tires had only 28PSI. I corrected the pressures myself after that -- I did complain about this to the body shop. Now, the alignment was done with these different tire pressures and with 4/32" tread-depth difference between right and left rear. Do you think I need a fresh 4-wheel alignment after I install a matching left rear tire?

My "S" is a daily driver. Any recommendation on what toe/camber/caster I should use in the front and rear that is optimal for daily driver without compromising its handling too much?

If I should post this to a different forum, please let me know.

Thanks.

Baskaran

dc2-2-ap1

^I am not an expert on alignments, but I would think you would be fine. There is a decent amount of "slack" (don't know what else to call it) with an alignment. Most places will not do them to a specific number/setting, instead, they go based off a predetermined percentage. Did they give you a printout of your alignment specs? If not, there is a chance the alignment is crap anyways. I am basing this assumption off of the fact they installed a new tire and didn't bother to check the other tire pressures- this is something most shops do even without getting an alignment. And secondly, if this wasn't a shop specializing in performance cars, they probably put in very little effort to spec it properly- because the average driver just wants it "good enough", they don't care about precision.
Most shops offer free alignments for 6months to a year after an alignment is performed. I would call them up and ask if they would be willing to recheck it.

As far as specs go, I am a fan of the uk spec alignment.

commander-data

Thanks for the reply to my alignment question. I felt that "Wheels and Tires by the Tire Rack" may not the appropriate place for this questions and asked the same question here in General Interest > S2000 Under The Hood. Please follow up there.

dc2-2-ap1

I think it would go in the brakes and suspension subforum.

commander-data

I replaced my left rear tire to match the new one on the right. I have put about 300 miles after that and I am happy to report that my car's rear end behaves much better now. It feels much better planted on the pavement when cornering and while going on rough patches.

Baskaran