I'd like to buy a set of replacement wheels for my 92 coupe and am wondering how important it is to adhere to the original factory wheel offset which, in my case, is 54mm. Based on that particular measurement, the selection of wheels available for my car is fairly limited. Most of the wheels I've looked at have offsets ranging anywhere from 45mm to 60mm. If I try to use wheels with more offset will they interfere with the brake calipers? If I go with less offset, will my tires rub the inside of the fenders and will the lugs extend far enough through the wheels to allow for safe mounting? If making contact with the fenders is an issue, can I resolve it simply by using a slightly narrower tire?

Any suggestions are much appreciated including recommendations as to some specific wheels that will work on my car.

Thanks ........... WS

 

Offset is relationship of wheel centerline with the mounting face where it bolts up to the hub; has no bearing on the thickness of the face where the studs fit

http://www.worldoneperformance.com/b...-offsets-work/

http://www.tirerack.com/wheels/tech/...jsp?techid=101

 

But if less offset moves the wheel center line further away from the hub isn't that going to result in less of the lug extending through the wheel? Be patient, I just may not be properly visualizing how this works.

 

Here is a chart.http://forums.corvetteforum.com/c4-t...set-chart.html

I have stock 9.5" rear sawblades and sent them in and had 1" added to the width inward, and am running 13" rear tires. I have 1/16" of clearance to the dog bones, Good place http://www.weldcraftwheels.com/
Don't go with 36mm Offset will stick way out. I will snap a picture how these look. Pricey

 

Consider a aftermarket 2 pce rim

The wheel center is bolted to the hub
The rim itself can be positioned ( offset ) anywhere in relation to the center
so in say the case of a 10" rim ;
it could be 5" + 5" ( zero offset )
or 6" + 4"
or 7" + 3" .
The center doesn't change

 

For starters it might be good to start with correct offsets. It's a minor difference but maybe important. Your '92 with 9 1/2" painted "saw-blade" wheels are 56mm offset. If you're attempting to compare wheels by just using the offset numbers you need to be working with wheels of the same width. Are you?

The chart referenced in #4 can be confusing particularly for someone that doesn't understand completely wheel construction. Simply put if you're dealing with wheels of the same width an offset with a "lower" number will move the tire/wheel combination towards the outer hood edge or quarter lip, a "higher" number would move the tire/wheel inboard creating less clearance to the suspension components.

56mm vs. 45mm would move the tire/wheel 11mm outboard and is generally considered aesthetically quite good and should create no issues. A 60mm wheel would move the tire/wheel inboard 4mm and result in 4mm less clearance to the suspension components, again should still be aesthetically OK.

If you want to measure just drop a plumb-bob from the outer lip of the hood to the ground at the wheel hub center and the same at the rear quarter lip and measure from the tire to the plumb-line. A lower number will move the tire/wheel closer, a higher I think you can visualize.

Any number less than those or greater than those you mention could be considered questionable BUT only if you're comparing wheels of the same width.

Do the plumb-bob measuring and learn - it's much easier than it sounds and much easier to visualize the potential results.

Offset has nothing to do with the wheel attachment to the hub BUT there are different style wheel nuts required for some after-market wheels - you need "CORRECT" hardware.

If you're comparing wheels of different width it's a much different effort.

The CF has a "COMPARISON CALCULATOR" that does quite well - spend some time with it and you can get quite proficient. I don't use it but it's there and can be very useful - the others referenced in this thread I don't use either. I'd suggest the CF because if you had questions everyone would be working with the "same tools"!

http://forums.corvetteforum.com/tire_rim_calculator.php

 

Thank you for the thorough explanation. That really does make it easier to understand. I also played around with the "calculator" and it looks like I will have more options to consider than I originally thought. As for 54mm vs 56mm, I was using a source located on the internet but as its been said before, you can't believe everything you read. Thanks again for helping out.

 

What was the approximate cost of the widening and what tires are you running?