so i finnally get the rear wheels for my z today and i overlooked 1 key factor TRACTION CONTROLL!! ... I am running a 18x9.5 inch rim with a 245 45 18 tire up front and 19x10.5 inch rim on the rear with a 275 30 19 inch tire what i failed to look at was the traction control would read the different tire rolling diameter so ..i figured i would ride without the traction control no big deal. but wen i hit a certain speed ... and maintain it the abs light kicks on along with the break warning lite .. what i would like to know is there a way around this problem ?? wat can i do or am i screwed

 

Yes, you can get correct size tires

 

+1 and their really not that hard to figure out.

 

thankz im such a dummmyy ... so simple i guess i was not thinking ... i love the guys on this site so helpfull

 

I know, hell your question was answered by the first person who responded.

Now you just have to look at your stock tire height and figure out what the + size tire should be for both your front and rear tire.

http://www.miata.net/garage/tirecalc.html this site helps, or you could search, cause those standard tire sizes get used all other the place in the tire section

https://my350z.com/forum/wheels-and-tires-60/

 

so... as long as the the two rims and tires have the same rolling diameters i should be good right?

 

No. Rears have to be slightly taller than front. Your rear tire is over an inch shorter than your front tire with your current sizes! It doesn't look awkward on the car?

 

your front rolling diameter needs to be a little less. Im not sure how much. Do a search on here. I seen something on it a few days ago. I might be wrong here but i think the front needs to be about 3% less than the rear. But i could be wrong.

 

Go to the link i posted and punch in your stock front tire size 225/45-18 and punch in the stock rear tire size, and then look at the difference. Guess what, you need that same difference in your aftermarket setup.

 

Front tires are taller than rear. It is a common mistake.

 

Agreed, OR, one can understand how to calculate their own total heights based on the numbers on the side of the tire:

275/30/19 = 275*.3 (Aspect ration) * 2 (top and bottom sidewall) / 25.4 to convert mm to inches + 19 to get total height in inches = 25.496"

 

your ABS/brake light has nothing to do with the traction control switch. if it was the TCS the TCS slip light would come on. you got other issues going on with your brakes

 

Actually ABS on our cars also uses the wheel speed sensers to determine if a tire is slipping. If the car doesn't have the proper sized tires (front to rear stagger in height) ABS can and will go into limp mode. If one of the two fails TCS/VDC and ABS thr other also locks out.

 

Again, the truly sad thing is that the OPs question is already answered in the Top 100 Questions thread.

 

yes very akward and i found a calculator just like the doge 1 posted and i will try to get a tire that is smaller for the front i think i will go with 235 40 18 thats as close as i can get them

 

Also just wanted to thank every 1 for thier imput weather posotive or negative

 

fyi, i have 235/40 18 fr and 255/40 18 rear, and my vdc light still comes on during occassional spirited driving, and stays on until the car is restarted.

 

obviously you havn't searched around a little here in the tire section. If you did you would have noticed that 245/40 and 255/40 are the two common sizes. Also if you run the calc program thats been posted for you , you may notice how close those two sizes are , 255 is less than 0.1 off fron stock tire height.

 

Im also not runing the same size rim there 19 in the rear and 18 front also i put 235 40 18 and 275 30 19 into the calculator and that will get me close ithonk its . 3 something

 

gotcha.