S650 Competition Package wheels on S197

Ski-dog

Junior Member
Joined
May 15, 2025
Posts
3
Reaction score
1
Location
Midland, Ontario Canada
Hi folks I’m new to this group and the owner of a low mileage 2006 GT convertible which is completely stock with exception of fluids and filters. Age of tires is a concern and was looking at storing original stock wheels and tires and getting a set of new take offs from a 2025 with competition package. I have been trying to get an answer whether these will fit which has been challenging. My searches popped up this forum and as such joined. Looking forward to keeping up to date here.

Has anyone installed S650 competition ( staggered ) wheels with success. Fronts are 255 / 40R19 and rear 275 / 40R19 from the S650, bolt pattern is same and from what I can find bore s same. Offset has not been confirmed but from what I could search fronts are +45 and rear +52.5

Thanks in advance

IMG_2802.jpeg
 

Racer47

Doesn't have much to say
Joined
Sep 11, 2009
Posts
1,092
Reaction score
337
Location
SE Wis
they will probably fit but to be sure i'd need the wheel width and offset
 

kazman59

King of Kazmania
Joined
Nov 9, 2016
Posts
491
Reaction score
241
Location
Kazmania
I believe there's a wheel calculator site on the interwebs that would help. Just can't remember it.
 

Racer47

Doesn't have much to say
Joined
Sep 11, 2009
Posts
1,092
Reaction score
337
Location
SE Wis
Front 9” with +45 offset
Rear 9.5” with + 52.5 offset
Centre bore 70.5 mm
Both of those are more offset than stock, meaning less flush, or more fender gap.

30 mm offset is ideal for 9" fronts. 45 mm will push the wheel in 0.6" farther. It should clear the strut and spring though with only 255 wide tires. You could add an 1/8" spacer to push it out some. Maybe 3/16" max before you have too few threads left on the stock lug studs.

Typical rear wheels are 10" wide with 45 mm offset. Using 9.5" with 52.5 ends up with the same back spacing, just 1/2" less wheel towards the fender. So the backs will fit for sure and could also use the 1/8" spacer.

This is what 9" wide 30 mm offset fronts and 10" wide 45 mm offset rears look like. Its not "tuner rubbing the fender lip" flush but it is what I think is the right amount of slight inwards offset from the fender lip.
wheel 1.jpg
 

fast Ed

Member
Joined
Nov 2, 2014
Posts
329
Reaction score
9
Location
Caledon, Ontario CANADA!
They’ll fit just fine. Front tires match with S197 OEM diameter, rears are a bit taller but not enough to cause any issues. Offsets for S197 and S550 / S650 wheels are all very similar other than the GT350 and GT500 variants.

Keep in mind going to the 19” wheels with shorter sidewalls causes a visual trick which makes your tire to fender gap appear larger (in comparison) even though the overall diameter of tires is similar. Good excuse to do some lowering springs and change out the dampers.
 

Ski-dog

Junior Member
Joined
May 15, 2025
Posts
3
Reaction score
1
Location
Midland, Ontario Canada
Hey folks really appreciate the help. Bullitt1011 the calculator is extremely handy. I was originally thinking they may poke out too far but looks like outside will be almost the same as stock. Not a fan of spacers but to Racer47’s info may need to consider some thin ones. And Fast Ed good point on the perceived look with reduced sidewall, I hadn’t thought of that.
 
Back
Top