i am replacing my tires with bfg kdw2s. the rear tire size i am going with is 255/40/18.

my question is should i go with the 235/40/18 or the 245/40/18 for the front? either size should work fine with the vdc, if i'm not mistaken. so what is the better front tire size for handling?

 

If you go with the 235, you will get more understeer than if you went with the 245 front. I just put on a set of the kdw's with 245 front and 255 rear on my track rims since i wanted more neutral handling, but since I haven't used them yet, I cant tell you how they are first hand.

 

I have KDW2 with a 235/255 combo it it runs great.

I don't really have any understeer issues. These are rain tires for me anyways, so understeer is a good thing.

 

kolia - taking into account that i use these wheels/tires for auto-xing, in addition to street tires, would you then recommend the 235 or the 245. I do have adjustable sways/shocks to neutralize the handling, so would it be better to just get the 235 then so they will also be better in the rain and less tram lining? my primary goal is handling.

sorry for the newb question, but this is the first time i've ever changed tires to a non oem size.

 

Are you on stock suspension? If so, going 245, 255 will give you more neutral handling and reduce the stock understeer that is dialed in. If you have upgraded suspension, your handling will be more neutral b/c of that upgrade, so sticking with the stock stagger of 20mm wider rear and going with the 235, 255 (also what I run in Azenis RT615) will be good.

Keep in mind for auto-X, as opposed to road racing, being able to whip the rear around with some oversteer is more desirable, so if that is your gaol, the 245 might be a better choice for you. I don't really think you'll have problems with either on the street.

 

my suspension set up is hotchkis sways and springs, and tokico d-spec shocks. i think i will go with the 235 and readjust the suspension if needed after installing the new tires.

thanks for the input.

 

Since you are going with 10mm over on the rear, I would follow suit in the front and go with a 235. I notice that with my 225/255 setup under hard braking the car is a bit unstable because the fronts lock up/lose traction before the rears. It’s nothing unsafe, the car just feels a little more "skittish" under hard braking. So to maintain that balance under hard braking, I would maintain the factory 20mm stagger.

Also, I need to drop that redline tranny fluid over today before I leave, so be ready...

 

We'll, if it's maximum handling you want, go for the 245. The difference shouldn't be that great but you'll still have that little extra grip on your side. For AutoX, it should be better.