Tire Sizes; 19 Front, 20 Rear

[w. mitty]

I'm considering upsizing to 19/20s. Considering either HREs or IForged. Just wondering if anyone as come up with tires that will match the rolling diameter of the factory setup for the 19/20 combination. I'm having trouble coming up with a match at the tire sites I have tried.

I know that a couple of owners here have done the 20/22 option, but that may be a little extreme for my tastes, at least until I see them in person.

 

[ROCMAN]

I'm considering upsizing to 19/20s. Considering either HREs or IForged. Just wondering if anyone as come up with tires that will match the rolling diameter of the factory setup for the 19/20 combination. I'm having trouble coming up with a match at the tire sites I have tried.

I know that a couple of owners here have done the 20/22 option, but that may be a little extreme for my tastes, at least until I see them in person.

Wherever you buy your wheels, they can suggest appropriate tire sizes.
If you want some IForged wheels, let me know and I will get you the homie price! :biggrin

 

[HAD2HAVE]

Wherever you buy your wheels, they can suggest appropriate tire sizes.
If you want some IForged wheels, let me know and I will get you the homie price! :biggrin

I'm intrested in the 19/20 combo as well. Could you please pm a price?

Thanks

 

[RWTD]

Okay, to determine the actual sizes of tires, here's the formula:

((X*Y/25.4)*2)+Z

Here is that broken down:

Tire Dimensions: For this example we will use a tire size of 315/40-19 (factory GT rear).

315 is the section width of the tire (how wide the tire is) in milimeters, dimension "X" in the diagram.

40 is an aspect ratio - from the top of the rim to the top of the tire (the sidewall, dimension "Y" in the diagram) is 40% as tall in that section as the tire is wide.

19 is the overall diameter of the rim, dimension "Z" in the diagram.

Our Example: X=315, Y=.40 (40% converted to decimal), Z=14

315 times .40 = 126

126 divided by 25.4 = 4.96"

4.96" times 2 (you have two sidewalls) = 9.92"

9.92" plus 19 = 28.92"

28.92 inches is the generally the overall diameter of a 315/40-19 tire.

As for the fronts, the 235/45-18 is roughly a 26.32" tall tire.

A quick check on the actual manufacturer's specs on these tires returns:

http://www.tirerack.com/tires/Spec.jsp?make=Goodyear&model=Eagle+F1+Supercar&tirePageLocQty=

26.3" for the front
28.9" for the rear

I hope this helps!

Regards,

James

 

[ROCMAN]

If you are not sure what color wheel you want, you can always go this route.

 

[STORMCAT]

www.1010tires.com has a great tire size calculator. You can check specs against stock size automatically. Look under the "tech" section on the left side.

 

[Jason Watt]

TRY_THIS

 

[fjpikul]

Ha, Ha, 101, you want us to put Miata tires on our cars so your's looks and goes faster?