badazzTL

Hi, I have a few questions:

1. How can I remove corrosion from a wheel's center cap? About half of the clearcoat is gone and where the clearcoat is gone there is corrosion. If I cant remove the corrosion, what type of paint do I use to repaint the centercap?

2. Someone told me that the odometer uses the speedometer to determine distance traveled. If I have a different size tire and my speedometer is off, my odometer will go up faster right? Is there any way to calibrate the speedometer to a different wheel size?

3. How much tire pressure is everyone running in aftermarket tires? On the acutal tire it says do not exceed 50 psi. I was thinking about only putting 35 psi or so in them. Will this be too little or just right?


thx in advance

TLMugen

To answer question #2:

Yes, a different size tire than stock will effect a speedo/odometer error; a smaller tire will show a higher speed than actual and the miles will therefore add on at a faster rate. I see by your signature that you went from a 205/60-16 stock tire in your TL to a 215/35-18. I took the liberty of plugging in those tire sizes into a tire size calculator (http://www.miata.net/garage/tirecalc.html) and it indicates a difference of 6.9%. This is a significant error.

There are devices available to correct the speedo/odo for differences in tire sizes but I don't know if there is one for the TL (too small a market). If you had a full size American truck (Silverado, F-150 or Ram) you'd be in business, there are ECU reprogrammers available for those popular vehicles that will correct for tire size changes (very common to change tire sizes; bigger diameter tires for 4x4s, smaller ones for street trucks).

Note: Tirerack.com suggests that tire upgrades stay within ±3% of original tire size to maintain a good degree of speedo/odo accuracy, if you measured the diameter of a certain tire size from different manufacturers (or the same manufacturer for that matter), you'd find variation there too so ±3% seems to be a commonly accepted variance. The correct 18" tire size for the 2nd gen. TL is 225/45-18, with a 1.1% difference in size.
Note: This is why Acura specs 215/50-17s for the TL-S. It's a wierd tire size but there's only a 0.9% difference in this Plus-1 upgrade from stock so they only need to use one speedo/odo set up for the two cars. OE mantra: Keep It Simple Stupid.

A non-scientific test would be the next time you're out on the highway and you see a mile marker, see how much earlier the mile clicks off. Then you decide whether you want to replace your tires with 225/45-18s.

Hope this helps.

My 2¢, spend wisely!

TLMugen

Might as well answer #3 as well!:

In the interest of maximizing tire life, I run 36 psi in the fronts and 30 psi in the rears because of the nose heavy bias of the car.

Whatever you use, periodically check the tire wear and adjust the tire pressure accordingly.

Another 2¢