If it were me, I'd buy the 949racing.com 6ULR 17x10 +52 wheels and Kumaho Ecsta ASX 255/40/17 tires. Total cost all new $1600 (There are no 265/40/17 all-season tires on Tirerack)

That way if you ever want to go to a BBK you still have options that will fit your wheel and you can always put Hoosier A6 295/35/17 tires on them if you want more tire to hit up the Track/AutoX in the future.

I think the sizing im getting is just right for a street car. It can fit the rubber I need and looks pretty good too ;) Im not too worried about fitting a bbk seeing as how Ill never make enough power with this car to overwork the stock brakes on the street. Im just looking for a fair ballance with the power/tire size/suspension settings.

SHIT! now they are telling me the offsets are 30........I have no idea if these will fit..... these wheel calculations are a real pita!

From previously posted link:

FRONT
Wheel Width Offset range Ideal
10 +50 to +52 +52
9.5 +44 to +56 +48
9 +37 to +63 +45

REAR Offset range Ideal
11 +48 +48 (will require fender roll)
10.5 +42 to +54 +48 (will require fender roll depending on tire size)
10 +35 to +61 +44
9.5 +29 to more than+60 +40



looks like rear yes, front no

18x9 +30 will be tight you will have to roll your fenders.

Do you think the fenders will need to be rolled even with the -1 degree of camber in front? I'm having trouble finding what the current offsets of my mazdaspeeds are but from what I gather its either 35 or 30 offsets. I would think these new wheels would fit about the same in the front, but I could be completely wrong!

http://www.wheelspecs.com/MazdaSpeed-MS-01_wm1511.aspx

Heres where I got my information. Mine are 17x8 in the front. These new wheels shouldn't be a problem then, right?

I would need the full specs on your MS-01's to be able to tell. What is the width? You can measure the offset pretty easily with the rims off the car. Just measure the distance from the mounting surface to the back side lip of the wheel and subtract half the width of the wheel.

Either way with 18x9 +30 according to the spreadsheets and seems to correspond with my experience you are around 3 mm into the fender lip.

17x8 +30 is roughly 71.6 mm from the mounting surface to the outer edge of your wheel.
18x9 +30 is roughly 84.3 mm from the mounting surface. So they will stick out almost 13 mm further then your current set up.

So from what your saying is it will stick out an extra 1.3cm?

1 inch = 2.54 cm
1 cm = 10 mm
1 inch = (2.54 x 10) mm = 25.4 mm

Little more then half an inch yo.

yes

Sweet baby Jesus my math is so fail....


Well I measured the distance from the fenders edge and my current wheel and Id say I have just about an inch. This might be a close fit, do you think I could pull it off without a fender roll?

It's to tight to say for sure. You could possibly get away with it, but I would plan on rolling your fenders.

Do you think its worth it to run a 9 inch wide wheel if its going to be this close? Im not really going for any of that hellaflush stuff.

Thats really up to you on what you want. You can run a 255 on a 8.5" rim so you could step it down in the front. However the Rota's only come in 18X8.5 +48 which is gonna be pretty sunken in in the front. Thats about 12 mm further in then your current set up. I'm not sure if the g-forces are concave or not, but if they are the wider they are the more concave they will be. Cast wheels like this will only have a couple "face designs" so offset will not affect concavity only rim width will. To achieve varying offsets they back fill the mounting surface.

if you plan on running no spoiler i think your better off with a staggered setup. If you plan on running a spoiler of some sort then by all means run the same size around. The same offets and size tire all around is almost guaranteed to cause over steer. A spoiler providing down force would balance that out. A staggerd setup can cause understeer depending on the the difference in tire sizes. i personaly do not like the feel of a staggered setup but if i had to pick a one i would do 17x10 and 17x9.5 both with 255/40/17s........ if u want same size all around and dont mind a bit of oversteer i would say 17x9.5 or 10 all around with 255s or 18x10 all around with 265s. there is almost no point in running 18x9.5s because you can easily produce similar results with 17s for almost half the cost.

Thanks for sharing:nod: