I have 2014 IS350 RWD with some mod and I would change my rear tire and wheels to 17".
Current, I am running a TE37 19X9.8+35 Front.

I am going to change the rear to 17x 9 ( WORK EMOTION T7R) 17X9+38 with tires 17x45x245.( Drag Race tires )

Now the question is a 4 centimeter difference higher of front ( 19x8.5 with 35 tire tall ) & rear ( 17x9 with 45 tire tall).

Will this difference makes any bad result or any issue ? I want to run them 17" only in drag race night.

How that 4 CM come?

I will break it down here
front is 19x8.5 wheels which is 483 mm tall
tire is 35 mm tall
total = 518 mm for front

rear 17x9 wheels which is 432 mm
tire is 45 mm
total= 477 mm

difference is
518-477= 41 mm= 4 cm

Thanks

 

So the rear tire will be lower 4cm.

 

Small adjustment to your calculation...the sidewall profile is a percentage (aspect ratio) of the tread width, not an actual measurement.
So, your front tire sidewall is 35% the size of the tread...which I'm guessing is either 225 or 235?
The rear drag tire will have a sidewall that is 45% of 245...which is 110.25mm,

What is the size of the tire on the front rims?

 

Front is 19" 8.5 +35 ( 235/35/19 )

 

Based on that the difference in tire sizes is marginal with respects to diameter and revs per mile.
You should be ok.

 

Another question

Do you think this tire size 245/45/17 will fit perfectly on 17" 7.5 ?

 

It can fit a 7.5 to 9 inch rim.

 

So I decide to go with

Gram light 57CR
17" 9J +38

M/T 245/45/17 ( ET STREET R )

What do you thinks guys ?

 

Or should I keep my rear wheel ( TE37 Ultra 19" 9.5 +35 ) and change the tire to TOYO R888R 265/35/19

Need your opinion guys.

Which route should I go !?

 

If you plan to attend drag race events with the vehicle, then having the proper dedicated rear wheels would be ideal to maximize the performance of the vehicle.
To carry 2 wheels to swap at the race site is certainly possible, even with the limited cargo capacity of the IS.

 

Thanks for the help

Just purchased the tire and it's ready

The wheels will arrive to me in July from Japan

Can't wait to install them and take a photo for you.

This is picture for the tire

 

I have just installed the 57CR with M/T slick tires