ayu910

Hi guys,

Just need to confirm my sc430 wheel tire setup, here is my plan:

20x8.5 +38 F (should be even with the fender and clear the caliper pretty well)
20x8.5 +25 R (should be even with the fender…caliper…too small…no need to worry about this)

245/35-20 all around. I know I know, tire size is not recommended b/c circumference is 1” more than stock. I plan to get this tire size for two reasons:

1. more tire wall area to cope with all the wonderful Bay Area potholes…specially this spring with heavy rain.
2. My friend is selling these tires for cheap but only that size.

Since I have Tein CS I think I will just raise my susp setup back to stock high or even higher to avoid front tire rubbing. Only negative is that I will need to perform corner weight and alignment again after change of susp high. Any suggestion welcome, thanks.

rominl

iTrader: (4)

um..... read my sc430 wheel fitment guy at the top

your setup will fit, but it's no way flush with fender, it's far from. you can push out the front for 20mm and still no problem, so you can imagine

Neo

iTrader: (3)

May I ask why you are doing this wheel setup? Is it to save on the tire cost? With the different wheel offsets, you cannot even rotate the wheels. In this case, you are not getting the benefits of keeping the wheel widths the same nor the benefits of wider wheels in the rear.

Also, 245/35/20 is only about 1" more than stock, not 4" (unless you are adding all 4 wheels together ).

ayu910

i did read the your wheel fitment guide which was very helpful and from my understanding in your guide 245/30-20 is not recommended tire size due to possible rubbing issue.

Cool, in this case I will run 20x8.5 +25 all around so I will have advantage of tire rotation. I plan to upgarde my brake in the near future, will +25 at front clear aftermarket brake caliper?

ayu910

thanks, u are right it should be 1"...I miss read the tire size comparison result from the miata site. I was worry to push the front +25 with bigger diameter (now I relaize it's only 1"....my bad) tire which might cause rubbing issue. thanks to rominl's info I realize I can still push the front more than 20mm so I will go with 20x8.5 +25 all around.

thanks for the help.

Neo

iTrader: (3)

While offsets certainly helps. it is not a guarantee for BBKs. Make sure the wheels are high disk. Spoke shape also plays a role.

rominl

iTrader: (4)

neo is right, the offset is good all around, but no gaurantee on the brakes. offsets has little to do with brake clearance, it's the disk type of how the spokes curve

and it's the other way too, with 245/30/20, you won't rub as much as 245/35/20. 245/35/20 is larger in overall diameter thus the higher chances on rubbing

sorry if i confused you

AZDesertGS

iTrader: (4)

Why don't you get the same offsets all around and then put a spacer on the rear so have it sit flush. This way you can rotate the wheels/tires. If your going to do different offsets you might as well go staggered.

rominl

iTrader: (4)

very well said, i agree with that. just get something that fits the front well, and put a small spacer in the back if needed

ayu910

thanks u guys are great!
I will go with 20x8.5 +25 with 245/35-20 all around so in this case I assume the back need 5~10mm of spacer to push it out a little? The front should look fine and almost even with the fender but might rube a little on the out side if car is lower than stock height.

is my understanding correct? thanks for the help