New Wheels and Tires

**Rhinohuey** · 06-15-2007, 08:53 PM

On my way to work today I ran through a big pile of some kind of 3/4" construction staples or something where someone spilled a box all over the road...anyway, all 4 tires are history.

A while back I bought a set of C5 wheels. I believe they are 2-17x8.5 and 2-18x9.5??? I don't have a clue how to measure what size they are...from the outside lip, or from the inside of the wheel... The numbers on the inside of the wheel are 17x8.5 and 18x9.5. Am I correct that these are the wheels' sizes?

My other question was, for tires I was thinking about the Nitto 555r Drag Radials and was wondering if this was a good tire for an everyday daily driver that sees the track about once a month or if there is a better tire? How long do they last compared to a street tire? About what will a full set cost me? Is the best place to buy them like a Discount Tire, or is there a better place?

I also need to know what size tires I need with the given wheel sizes. I read that 275-35-18 are appropriate for 18 inch wheels and 275-40-17 are appropriate for 17 inch wheels for the reason that they don't throw off the speedometer or screw with the ABS but I noticed on Nitto's and Discount Tire's website that they don't offer these sizes, so I'm not sure what sizes I need to go with. Thanks for your help.

**Rhinohuey** · 06-15-2007, 08:55 PM

Oh sorry, one other question. Will the dealership correct the speedometer for different tire diameters (if I will have different diameters) or will I have to find someone else to do the tuning for that?

**mrr23** · 06-16-2007, 01:22 PM

yes. those are the correct sizes cast into the wheels.

i run the nitto 555 tires on my car. proper tire size to use that will not affect the speedo is

245/45-17 nitto 555 front 25.7" tall (factory tire height)
285/35-18 nitto 555R drag radial rear 25.9" tall

the .2" difference won't be enough to matter.

**Rhinohuey** · 06-16-2007, 03:09 PM

If I bumped the rear tires up to either a 275/45 or a 285/45 (they don't make a 40 ratio right?) to make is so the rear tire doesn't look smaller than the front tire, that would be about a 1" differnece from the fronts correct? If I did go this route, would the dealership do the required tuning to make the speedo correct or would I have to find someone else? Also if I have the ABS issue (if I do it this way) is that fixable through the dealership or through a handheld or not?

**mrr23** · 06-16-2007, 03:12 PM

they make a 275/40-18. come on the vettes. this will be a 1.4" difference. don' know if a dealership can change the tire diameter in the PCM. the ABS issue cannot be fixed to compensate for different height tires on the f-bodies.

**Rhinohuey** · 06-16-2007, 03:27 PM

The ABS has its own fuse that I can pull right? If so, will pulling the fuse get rid of the ABS problems associated with having larger tires in the rear? (I plan on a new 12 bolt or 9" sometime down the road and don't want to mess with the ABS stuff anyways)

**mrr23** · 06-16-2007, 03:32 PM

then have at it

**Rhinohuey** · 06-16-2007, 03:33 PM

So pulling the fuse won't give me any problems and it will disable the ABS completely, right?

**Rhinohuey** · 06-16-2007, 03:39 PM

Dang!!! Nevermind, I'm getting confused with the traction control. I can't get rid of the ABS. I'm going to have to think about this a while before I buy tires.

**Rhinohuey** · 06-16-2007, 03:53 PM

Anyone want to trade 2 of my Polished C5 17s for 2 of their Polished C5 18s or the other way around? Haha

**Eugenio_SS** · 06-16-2007, 07:34 PM

Originally Posted by Rhinohuey

The ABS has its own fuse that I can pull right? If so, will pulling the fuse get rid of the ABS problems associated with having larger tires in the rear? (I plan on a new 12 bolt or 9" sometime down the road and don't want to mess with the ABS stuff anyways)

not as simple as that... ABS also sets the f/r bias ratio for braking... with abs not working, you get too much rear brake bias and the car won't brake as well... you'll end up locking the rear wheels easily, and not being @ full braking power in the front.
do it right and bypass the Abs + put a proportioning valve.