Dr Bonz

iTrader: (1)

Well, I have asked 4 or 5 different people this question and I now have nearly as many answers.

I hope that posting here to all the experts will allow me to arrive at a consensus.

I am ready to purchase a set of wheels. I am getting the Racing Hart CFT Tunes. These are 9.0 front and 10.5 rear.

I have decided (after listening to several folks whom I know and respect here) to go with the BFG G-Force T/A KDW's.

Now, here is my question.

I want to go with as wide a tire as I can (wide as in width not sidewall) for these wheels without having to roll the fenders and that will not mess with the Traction Control.

I think I have it nailed down (a consensus among those I have asked) to the 245/35/19's for the front. Although one person said I could go with the 255/35/19 in the front.

I still don't know what to go with for the rear however.
Here is what I have been told

275/35/19
285/35/19
285/30/19

CAN SOMEONE PLEASE HELP ME HERE. I am VERY confused.


Also, just a concept question for my own private knowledge. When they refer to the sizes of aftermarket tires needing to be similar to the stock tires so as to not mess up the traction control, what size are they referring to exactly? Is it the total height of the tire? The width? The height of the sidewall?

I REALLY appreciate some help here guys!

Thanks

rodmanj

Dr Bonz I feel your pain. But mine are with 17's and not 19.
I too have researcged and listen to many posters on this site.
So while the experts are reviewing your question I hope they can answer mine.

With the exception of the Speedometer what are the pro and cons of going with these tires sizes.

from Front 225/50 R17 to 245/45 R17
from Rear 235/50 R17 to 255/45 R17

Thanks in advance all.

1nate7

iTrader: (19)

The 245/35 and 275/35 combo is very popular but if you want a wider tire I would run 255/35 and 285/35. Very close to the stock overall diameter and fits the wheels nicely. Also gives you a little more sidewall to protect the rims/fill out the wheel well.

Dr Bonz

iTrader: (1)

I was under the impression (I certainly could be and probably am wrong) that the first number (the 245 vs 255) referred only to the width of the tire in mm (in other words, the contact patch width). I thought that the second number (the 35) referred to the sidewall to width ratio and that it was THIS number that would effect the diameter and wheel well fill.

Am I wrong?

Anyway, can ANYONE out there clarify what tires I need here?

1nate7

iTrader: (19)

You're not wrong. 35 is a %, sidewall height compared to tread width. 35% of 255/285 mm is bigger than 35% of 245/275, giving you slightly more sidewall.

Dr Bonz

iTrader: (1)

OK Thanks.

JCat

iTrader: (4)

Go here and plug in your current tire sizes:

Discount Tire

Print it out.

Then, plug in what tire sizes folks have suggested to you. You will see the exact differences in the various tire dimensions.

going deep

Dr. Bonz,
I recently bought Volks SF Challenge, in 19x9.5 front with +23, and 19x10.5 rear with +23.
And I bought the same tire brand as you, but I decided to go with 245/35r19, 285/35r19. I have been assured by my sponsor thats been selling wheels for many years that I will not have rubbing issues. I think one of the reasons that 275 in the rear is so popular, is because the tires are generally cheaper to buy. Also, some brands of tires do not make 295s for 19inch wheels. The tire calculator that was previously posted will definately help you determine what the new tire/wheel combo will do to your ride height and speedometer.


Ernie

lowrider

iTrader: (3)

Dr. Bonz

To correct another ereror in your thinking: the first number does not refer to the width of the contact patch, but to the width of the tire at it's widest point (the sidewall measurement - sidewall to sidewall). Many tires (different brands, or models withen that brand) displaying the same size, will have different tread widths (contact patch). As you state, the aspect ratio is the percentage of the tires sidewall height to the width of the tire.

With all that being said, I would stick with the tried and true 245/35/19-275/35/19 combo that works so well on the "Z". It maintains the stagger and does improve the handling characteristics of the automobile. Both tires are much wider than stock, and with the proper width and offset wheels, do give the car that big tire look you're looking for, without going overboard.

JMO

Lou

Dr Bonz

iTrader: (1)

Thanks a lot everyone. I will digest all of this and make the decison.