Miamiboy87

I got my car lowered on Tanabe's and i'm liking the F-sport rims on it, but looking for a new look. The tires I have are pretty new and came with the car when I purchased it about 5months ago. Initially I wanted to go +1 which meant new tires also. I like how it looks as of now with 17" and don't really see a need to purchase new tires so I may just wrap new 17" rims on the current tires. My question is, and from what I have seen, the rims to purchase are 17x8 or 17.8.5 . The tiresI have are size 215/45/17 x7 . Does this mean the rim can't be 17x8 or 17x8.5?

Mutorcs

Well if you can this should definitely give a "stretched" look to your tires.

With my 17x7.5 rims I had to go with 225/45/17 tires so they could be homologate here in Switzerland.

Miamiboy87

Won't that be bad for the tires? .5 an inch seems excess stretch to me, especially overtime, but i don't know anything about tire sizing etc.. Basically, would I have to get rims that are 17

oldwineguy

I am assuming you would get the same +45 offset. There would be not any stretch with the 215/45 on a 8" wheel and almost non existent on an 8.5" rim. Here is a site that might help you, i plugged in a 8" wheel on this link, but you can try different combinations
https://www.wheel-size.com/calc/?whe...cl=50mm&sr=0mm

Miamiboy87

Thanks. I noticed that a lower offset, like 38 gives it a positive scrub radius, that would affect handling.. I guess I can stick to something similar to the stock offset.

oldwineguy

The scrub radius is the distance in front view between the king pin axis and the center of the contact patch of the wheel, where both would theoretically touch the road.
The kingpin axis is the line between the upper and lower ball joints of the hub. On a MacPherson strut, the top pivot point is the strut bearing, and the bottom point is the lower ball joint. The inclination of the steering axis is measured as the angle between the steering axis and the centerline of the wheel. This means that if the camber angle is adjustable within the pivot points the scrub radius can be changed, this alters the width and offset of the tires on a vehicle.
If the kingpin axis intersection point is outboard of the center of the contact patch it is negative, if inside the contact patch it is positive. The term scrub radius derives from the fact that either in the positive or negative mode, the tire does not turn on its centerline (it scrubs the road in a turn) and due to the increased friction, more effort is needed to turn the wheel.
Large positive values of scrub radius, 4 inches/100 mm or so, were used in cars for many years. The advantage of this is that the tire rolls as the wheel is steered, which reduces the effort when parking. This also allows greater width in the engine bay, which is very important in some compact sports cars.
If the scrub radius is small then the contact patch is spun in place when parking, which takes a lot more effort.
The advantage of a small scrub radius is that the steering becomes less sensitive to braking inputs, in particular.An advantage of a negative scrub radius is that the geometry naturally compensates for split µ (mu) braking, or failure in one of the brake circuits. It also provides center point steering in the event of a tire deflation, which provides greater stability and steering control in this emergency.