Super_Dude

I was just looking around at differnt wheels and noticed that alot of the mazdaspeed parts are ~+40 instead of the +50 on the stock wheels. I know alot of race cars use offsets to fine tune handling but then that raises the question of why almost all CCW's or fiskes equiped FD's are running +50. any info back would be great. (PS don't say the mazda speeds arent for racing cause there 18 inch mag wheel is +40)

Eggie

CCWs must be +50 to fit 10"-wide wheels under the stock fenders. The MS wheels are, what, 8.5"? So they can fit with the lower offset.

treceb

If i recall my set of MS01s is 17x8 +32 and 17x9 +35 and the MS02s are 17x8 +38 and 17x9 +38.(im 90% positive or at least close on those offsets)

Super_Dude

That doesn't really answer my question. my question is if +50 is the ideal offset, y is mazdaspeeds rims +40? is the increase in track more important than the increase in scrub radius? Im really hoping an expert will tell me

aznpoopy

offset is a fairly useless number independent of width

you can't determine how it affects scrub radius and overall track unless you pair that number with a width

just because a wheel has a lower offset doesn't automatically mean it gives the car less steering clearance and a wider track base

Eggie

I have to disagree.

Track width is the distance between the center of the tires' treads, so it is most definitely all about offset. Any wheels with +50mm offset will have the same track as stock on an FD. Doesn't matter if they're 7" or 10" wide, offset specifies the tires' locations.

And the same goes for scrub radius as well. The wheel's width doesn't affect it at all, because the radius is measured from the center of the tread. Scrub is affected by other factors (e.g. tire diameter), but offset is the most significant number.

aznpoopy

i stand corrected

treceb

my guess is that since mazdaspeed wheels were made specifically for the car, they used the optimum offset/rim width that cleared the caliper/fit the wheel wells.