I was planning to fit my OEM wheels with 225/55 R17 F1 GS-D3 when the tires are gone. Recently my friend suggest that I go got the 45 side wall instead of 55 because it would help the car corners better. I know this is true but I am just wondering what are the potential problems except for a wrong reading on the dash.

 

anyone wanna reply?

 

A 45 profile will certainly throw your speedo off about 5%; this loosely translates to more miles on the odometer than you've actually driven. For every actual 100 miles driven, the odometer will indicate 105, that's 500 miles extra on the odo for every 10K actually driven.

The lower profile will also give you a MUCH harsher ride over a 55 series of the same brand. This can be a problem if there are potholes in your part of the country; the lower the profile the less protection the rim gets, higher profile tires tend to absorb the impact much more.

Also, just because a tire is a lower profile does not mean that it WILL provide better cornering; the actual makeup of the sidewall determines the tire's handling characteristics, and this varies from manufacturer to manufacturer. In fact I suspect that any increase in road holding ability a lower profile tire gives you will be so neglible that you won't notice. Also, have you ever seen the height of actual racing tires? I do not remember seeing low profile tires being used....

Disclaimer... I'm no tire expert... just my 0.02. Do a little reading and do whatever seems to make the most sense to you.

P.S. Consider 235/50/17 as well, you still get a lower aspect ratio but a wider tire. My "layman's" belief always tells me that wider tires, the more rubber on the road, offers more grip in a straight line as well as around corners... cent # 3.


<font color=red>chinee</font color=red>
03.5 G35s

 

A 45 profile will certainly throw your speedo off about 5%; this loosely translates to more miles on the odometer than you've actually driven. For every actual 100 miles driven, the odometer will indicate 105, that's 500 miles extra on the odo for every 10K actually driven.

The lower profile will also give you a MUCH harsher ride over a 55 series of the same brand. This can also be a problem if there are potholes in your part of the country; the lower the profile the less protection the rim gets, higher profile tires tend to absorb the impact much more.

Also, just because a tire is a lower profile does not mean that it WILL provide better cornering; the actual makeup of the sidewall determines the tire's handling characteristics, and this varies from manufacturer to manufacturer. In fact I suspect that any increase in road holding ability a lower profile tire gives you will be so neglible that you won't notice. Also, have you ever seen the height of actual racing tires? No low profile tires are used....

Disclaimer... I'm no tire expert... just my 0.02


<font color=red>chinee</font color=red>
03.5 G35s

 

Think twice before going wider than stock, unless you're going more for show than go. If the wheel is too narrow for the tire, it will contort the contact patch and traction will actually reduce. Wish they hadn't put those wimpy-a@# wheels on the sedan.

 

Exactly!!! These tires are certainly not the best tires in the world. Well a lower profile will most likely have less room for the tire to compress during cornering over higher profile tires. That is one of the reason why most sports car have 245 and down EXCEPT FOR THIS ONE. Ugh......... If I had the money, I wouldn't deal with this issue right now.

 

I can also think about 235/45 R17 which is about 3.7% faster than stock. Not very much but I still get a 45 sidewall. Another reason I want a 45 side wall because it has more choices no matter its 215, 225 or 235. the 50 sidewall only has Pilot Sport A/s and the OEM tires only got Turanza and .............. whatever those are.

 

I would recommend sticking to 235/50R17, or 225/55R17, or 225/50R17.

I wouldn't go outside +/- a 3% difference from the stock tire diameter, except for race-day-only tires. A 235/45R17 would have been a nice size for this car, but oh well. If you could get someone to recalibrate the speedometer, this would be a good size to set it to.

We do have a member (lead_foot) running 245/45R17 Falken Azenis on his car, on the stock rims (even though that tire technically requires a 7.5" rim).

The 225/55R17 size gives you the Eagle F1 GS-D3's and the Bridgestone Pole Position S-03's, both excellent tires, even in a 55 series. I'm running the F1's on my car now, I had the Turanza's on it before, and it's an incredible difference.

 

I know I know.
I was thining about 225/55 R17 F1 GS-D3 before and I was thinking of getting it during a weekend where I can drive down to the states from Vancouver to get it.
But the idea of a thinner side wall really attracted me and I just wanna see if I should do this.
I heard GS-D3's sidewall is a little soft too, so thats why I wanna have a thinner sidewall to make sure it doesnt compress too much when I enter a corner.

 

bump
<P ID="edit"><FONT class="small"><EM>Edited by Renesis on 05/17/04 12:12 AM.</EM></FONT></P>

 

bump

 

If you're going to be driving that hard, you should stick 38-40psi in the tires. The ride gets rather harsh and bumpy, but it keeps the sidewall from rolling under. That's what I do for autocross days, but I let it back down for the streets.