Needing some one familiar with wheels to answer a question.....

Looking to buy some Competition Gray wheels for my '02 Black Z06... But I do not understand "offset" language....

Is there a standard for 'offset' with the C5 Z06's? May be wrong here, but back in the day I had bought a new '02 MY Z06 and the new '04 Comm Ed...... When I had the wheels off for detailing, I recall seeing an offset number stamped on the inside of the factory wheel....

Guess my question would be, when I begin to get really serious on buying the new wheels, Will they have to have the same "offset" as the factory wheels have?

Crazy question eh? But really need educated here.....

 

Offset describes where the hub is in relation to the rest of the wheel.



Stock Z06 offsets

Front - 54mm
Rear - 58mm

 

all you need to know here.

 

I just finished a coupla weeks' worth of searching for a snazzier wheel, but settled on polished OEM because of the weight. In my search, I found this info:

Front Offset: +54mm
Front Backspacing: 7.38"

Rear Offset: +58mm
Rear Backspacing: 8.03"

For a description of offset: http://www.tirerack.com/wheels/wtpack.jsp

and backspacing: the * footnote at the bottom of the referenced article

I found that a lot of wheel companies don't provide their wheels' offsets, but they do define their wheels' backspacing.

From what I found, most of the "mid-range" priced wheels ($400-700 each) are listed with a "tolerance"--say, just as a WAG, 6"-8" backspacing. They'll all "fit", but not specifically to the exact 7.38" of the C5 Z06's front dimension.

If you get into the high-line wheels (HRE or Fiske for example, @ ~$1200+ each) those will be custom-built to your specifications. At least, that's the website claim on their applications form. The only problem with even the HRE's was that comparable sizes were still heavier than GM OEM weights. I found that a surprise. Comparing aftermarket wheels against the OEMs only for their unsprung wheel weight will be very hard to beat with 'moderate' funding.

Be careful with adding unsprung weight. Surf the net for tests and anecdotal info. +4lb each can supposedly render handling ugly. Somewhere in TireRack's website they have a survey they conducted where they only changed out wheels to change their weights as I recall, and then they drove them to gauge handling and wrote it up. I fell in love with Billet Specialties SLG 45's; take a look at them--pretty wheels--and at least 8 pounds heavier apiece. Sometimes with the right tire choice (by weight) you can compensate for the wheel's extra weight, but at best it's usually only just that--a compromise, because the tire's tread isn't the ideal for such a car.

I found it! http://www.tirerack.com/wheels/tech/...sp?techid=108&

 

Thanks for all the good info!! That helps a ton..!!

Zeeman

 

Here's a nice tool to play with.
http://www.rimsntires.com/specs.jsp

 

Your link is hosed up ... this one is for Offset.
http://www.tirerack.com/wheels/tech/...jsp?techid=101

Here's all of Tire Rack's wheel tech stuff.
http://www.tirerack.com/wheels/tech/index.jsp

 

This is why offset is critical ... especially if you plan on putting wider wheels and tires on the car. The offset and width of the rim will determine how close the tire is to suspension components etc on the inside surface of the tire, and it will also determine how far the outer surface of the tire fills up the wheel well, or sticks out beyond the fender lip.

http://www.tirerack.com/wheels/tech/....jsp?techid=95