[Tom White Coupe]

I have been researching larger wheels for my coupe an discovered that 5x110 e55 is unusual. (Shame on GM), I think any 18/19x9.5 with 45 to 52 offset and 275x40/35 tires will fit. There are many available in these sizes for Audi, Mercedes, and BMW w/ 5x112 PCD. (Many staggered).
In Europe, bolting wheels on is common, US tends to use studs. They use "wobble bolts", a shoulder bolt with a loose, cone shaped washer to mount 114.x (Ford) wheels on 5x112 cars. Look them up on the eBay.UK sight. As all wheels should be hub centric, that is located on the hub, any bold that is straight and torqued correctly will hold the wheel in place. Friction keeps the wheel from moving, not shear on the bolts. Some of you have seen what happens when wheel nuts come loose and you start using bolt shear to hold the wheels in place. Wobble nuts with hub centric rings should be a good alternative to "special" wheels or re-drilling hubs. Unfortunately, 114.x SVT Mustang wheels will not fit on a 5x110 hub w/o re-drilling. Beware, some Mercedes use a ball shaped bolt instead of a taper bolt.
1. If you have a friend with 5x112 wheels/tires, you could try them on just to see how they look and fit. Please do not drive them w/o wobble nuts and hub centric rings.
2. Please post pictures of what fits.

 

[Tom White Coupe]

Wobble Bolts: Nuts | eBay

PCD WOBBLY CORRECTIVE NUTS M12 X 1.50 SET OF 20 | eBay

 

[Tom White Coupe]

Most aftermarket wheels for VW, Audi and Mercedes, (5x112) with appropriate hub centric rings, will fit a Kappa. Most OE VW and Audi hubs are smaller, requiring adapters or boring out the wheel center.
The following was gleaned from Wheel Bolt Pattern Cross Reference Database and Conversion Guide
Make Model Year Bolt Pattern Stud Size Hub Center Bore
CADILLAC CATERA 1996-02 Metric:**5*X*110 12 X 1.5* 65.1*
CADILLAC CATERA 1997-01 Metric:**5*X*110 12 X 1.5b* 65.1*
CHEVROLET COBALT SS, SPORT 2005-08 Metric:**5*X*110 12 X 1.5* 65.1*
CHEVROLET HHR 2006-08 Metric:**5*X*110 12 X 1.5* 65.1*
CHEVROLET MALIBU (ALL) 2004-07 Metric:**5*X*110 12 X 1.5* 65.1*
CHEVROLET/GMC MALIBU 2004 > Metric:**5*X*110 12 X 1.5* 65.1*
PONTIAC G5 GT 2007-08 Metric:**5*X*110 12 X 1.5* 65.1*
PONTIAC G6 BASE, GT 2005-08 Metric:**5*X*110 12 X 1.5* 65.1*
PONTIAC SOLSTICE 2006-08 Metric:**5*X*110 12 X 1.5* 65.1*
SAAB 3-9 COR 1999 > Metric:**5*X*110 14 X 1.5* 65.1*
SAAB 5-9 COR 1999 > Metric:**5*X*110 14 X 1.5* 65.1*
SAAB 9 3 1999-08 Metric:**5*X*110 12 X 1.5* 65.1*
SAAB 9 4 1993-98 Metric:**5*X*110 12 X 1.5* 65.1*
SAAB 9 5 1999-08 Metric:**5*X*110 12 X 1.5* 65.1*
SAAB 900 1994-97 Metric:**5*X*110 14 X 1.5* 65.1*
SAAB 3-Sep 1999 > Metric:**5*X*110 14 X 1.5* 65.1*
SAAB 5-Sep 1999 > Metric:**5*X*110 14 X 1.5* 65.1*
SATURN ASTRA 2008 Metric:**5*X*110 12 X 1.5* 65.1*
SATURN AURA XE, XR 2007-08 Metric:**5*X*110 12 X 1.5* 65.1*
SATURN ION REDLINE 2005-07 Metric:**5*X*110 12 X 1.5* 65.1*
SATURN L SERIES 1999 > Metric:**5*X*110 12 X 1.5* 65.1*
SATURN L SERIES 1999-05 Metric:**5*X*110 12 X 1.5* 65.1*
SATURN SKY, SKY REDLINE 2007-08 Metric:**5*X*110 12 X 1.5* 65.1*
Make Model Year Bolt Pattern Stud Size Hub Center Bore
AUDI A5 2008 Metric:**5*X*112 14 X 1.5b* 66.6*
AUDI S5 2008 Metric:**5*X*112 14 X 1.5b* 66.6*
CHRYSLER CROSSFIRE 2004 > Metric:**5*X*112 12 X 1.5b* 66.56*
CHRYSLER CROSSFIRE 2004-08 Metric:**5*X*112 12 X 1.5b* 66.56*
MAYBACH 57 2004-08 Metric:**5*X*112 14 X 1.5b* 66.56*
MAYBACH 57S 2004-08 Metric:**5*X*112 14 X 1.5b* 66.56*
MAYBACH 62 2004-08 Metric:**5*X*112 14 X 1.5b* 66.56*
MERCEDES BENZ 107 CHASSIS ALL Metric:**5*X*112 12 X 1.5b* 66.1*
MERCEDES BENZ 116 CHASSIS ALL Metric:**5*X*112 12 X 1.5b* 66.1*
MERCEDES BENZ 124 CHASSIS ALL Metric:**5*X*112 12 X 1.5b* 66.1*
MERCEDES BENZ 126 CHASSIS ALL Metric:**5*X*112 12 X 1.5b* 66.1*
MERCEDES BENZ 129 CHASSIS ALL Metric:**5*X*112 12 X 1.5b* 66.1*
MERCEDES BENZ 140 CHASSIS ALL Metric:**5*X*112 14 X 1.5b* 66.1*
MERCEDES BENZ 163 CHASSIS ALL Metric:**5*X*112 14 X 1.5b* 66.1*
MERCEDES BENZ 170 CHASSIS ALL Metric:**5*X*112 12 X 1.5b* 66.1*
MERCEDES BENZ 201 CHASSIS ALL Metric:**5*X*112 12 X 1.5b* 66.1*
MERCEDES BENZ 202 CHASSIS ALL Metric:**5*X*112 12 X 1.5b* 66.1*
MERCEDES BENZ 203 CHASSIS ALL Metric:**5*X*112 12 X 1.5b* 66.1*
MERCEDES BENZ 208 CHASSIS ALL Metric:**5*X*112 12 X 1.5b* 66.1*
MERCEDES BENZ 210 CHASSIS ALL Metric:**5*X*112 12 X 1.5b* 66.1*
MERCEDES BENZ 215 CHASSIS ALL Metric:**5*X*112 12 X 1.5b* 66.1*
MERCEDES BENZ 220 CHASSIS ALL Metric:**5*X*112 14 X 1.5b* 66.1*

 

[idkfa]

I've been asking this for a few years. Still have yet to see anyone try but it should be doable... and there are so many more options at 5x112.

 

[sirwm]

interesting...

I remember these from the days I had a '72 VW...

 

[AaronJ]

Do any of those wheels even look good? I know all of those 5x110 wheels listed up there are not wider than 8". I take it hub swaps must not be popular with Kappas? I know Deltas (Cobalt/Ion) they are pretty popular for people to swap their hubs and rotors to 5x114.3.