tire side wall Measurement question

[Kalisko]

Say I wanted to get a 235/60r18 (18x8 wheels) on my GSX.
It is not lowered and I have tons of room under my wheel wells.

Right now I have 225/40r18
If I add the extra 2 inches of sidewall, that is the HIGHEST point in the tire right? including the center?

I'm asking because I'm trying to fill the wheel wells as much as possible, and I'm going to get a nice meaty tire (Figured with AWD it'd be sexy and I can avoid pothole rubs killing on first touch)

Has anyone else ran these sizes before on the stock suspension?
Here's a couple photos of the current (CRAPPY) tires with the extra space.

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and here's a picture of the type of tire I'm planning on getting. It's a meaty sob but I think it'll look nice and handle good for all season. I have another set of wheels with performance tires but I don't really need fast tires, something that handles great on all terrains due to living out in the boones.

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[timm98gst]

this should help you compare:
Tire size calculator
looks like it would be quite a significant difference

 

[lilbro717]

it will also lift your car quite a bit

 

[Kalisko]

Yeah I think I'm going to downgrade to 15" or 14" wheels and get some big tires. It'll be an extra 3/4 of an inch in total diameter.

I'm pretty sure I'm going for the 14" wheels with 225/70R14' Tires. It'll only lift it up another 3/4 of an inch. I want my AWD Car to not be slammed, so Im' ok with ride height

 

[99redgst]

Your not going to fit 14" wheels over the dual piston calipers, I'm not sure that 15s would either. You can not increase the tire diameter much from stock. The wheel well is not the limiting factor, the spindle is.

 

[myturbo]

tires are measured in MM. for example - 225-40-18 .= 225 mm wide, 40% of 225mm, and an 18 inch rim

 

[Kalisko]

Your not going to fit 14" wheels over the dual piston calipers, I'm not sure that 15s would either. You can not increase the tire diameter much from stock. The wheel well is not the limiting factor, the spindle is.

Good call, I forgot about the inside of the wheel LoL.. I'll take it down the road to the tire shop and see if it'll fit, but I think you're right.