# 18" rims



## sig229 (Sep 21, 2005)

Can anyone tell me whether the 18" rims improve performance in some way or are they just for looks.


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## Good 2 go (Sep 7, 2005)

They come with summer performance tires, while the 17" wheels have all-season tires. I have yet to see a review on a GTO with the 18's, but I'm sure there is a performance diff.


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## ftlfirefighter (Jun 6, 2005)

The shorter side wall of 18's improves lateral performance, handling, because of less flexing. I run 19's with a 35 series tire and it was a MAJOR difference than stock. Granted they ride ruffer but all the "squisheness" is gone when throwing the car into a turn. They look like thin rubber bands but that's part of the appeal also. Go with the Lightest wheel and tire combo as possible to reduce unsprung weight. BBS RGR weigh only 20 pounds per wich is some 10 lbs lighter than stock. The Michelin PS2 is also in the low 20lb per class. Rotating mass greatly affects handling and braking so the lighter the better.


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## dtor (Sep 17, 2005)

ftlfirefighter said:


> The shorter side wall of 18's improves lateral performance, handling, because of less flexing. I run 19's with a 35 series tire and it was a MAJOR difference than stock. Granted they ride ruffer but all the "squisheness" is gone when throwing the car into a turn. They look like thin rubber bands but that's part of the appeal also. Go with the Lightest wheel and tire combo as possible to reduce unsprung weight. BBS RGR weigh only 20 pounds per wich is some 10 lbs lighter than stock. The Michelin PS2 is also in the low 20lb per class. Rotating mass greatly affects handling and braking so the lighter the better.


Is the outside diameter of the 19" tires the same as the 17" stockers? If not, do you get any rubbing or did you have to roll your fender lips? How wide are your 19"s?


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## ftlfirefighter (Jun 6, 2005)

The overall diameter is .1" greater than stock. No rubbing with 8.5's f & r. I'm running 245/35-19 Michelin PS2's.


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## 05GOAT (Nov 11, 2004)

I run the below combination with Toyo Proxes T1-S's. The grip is so much better than the stock as well as the cornering. Not to mention all the compliments I get. There are pictures under My Goat above the Signature picture. ROH wheels are from Australia. You do not have to roll the fenders and it lowers the car a little.  

Recommendation for 18" wheels: Without a doubt the best set is 18x8 up front with 245/45/18 matched with 18x9 out back w/ 275/35/18. This set looks great, fits porportionally and lets you pick up some width out back. The ride quality is also great. Or use 18x8 and 245/40/18 at all four corners.

ROH Drift R 18x8 w/ a 245/40/18 tire - 49lbs
ROH Drift R 18x9 w/ a 275/35/18 tire - 51lbs


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## sig229 (Sep 21, 2005)

My 06 has 18's. Why do they drop down to 235 when they go up to 18's? thr 17's are 245. Seems a little strange to me. When i replace the tires can i put 245's on them? will it change anything?


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## ftlfirefighter (Jun 6, 2005)

I think it has something to do with the diameter. 40series = 40% of 235 vs 245.


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## sig229 (Sep 21, 2005)

i understand the concept of tire profile. My question is why when they bump rim size up an inch did they reduce tire width (not profile) down?


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## ftlfirefighter (Jun 6, 2005)

Hey sig, that's a good question. I just did some math and the 235/40-18 is .3" shorter. A 245/40-18 is exactly the same diameter as the 245/45-17. So who knows why they went narrower.


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## NoBMWforME (Apr 12, 2005)

Sorry, I'm being lazy here and did not do a search of the archives, does anyone know the weigth of the stock wheel with the tire? I too am waiting for the staggered ROH Drift R setup to arrive and want to know if there is a big diff in unsprung weight with these wheels.

Thanks.


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## Groucho (Sep 11, 2004)

NoBMWforME said:


> Sorry, I'm being lazy here and did not do a search of the archives, does anyone know the weigth of the stock wheel with the tire? I too am waiting for the staggered ROH Drift R setup to arrive and want to know if there is a big diff in unsprung weight with these wheels.
> 
> Thanks.



Good question...heck, I'm having a hard time determining the weight of my MOMOs...of course, I could take them off and _weigh_ them...

Nah. That reeks of _work_.


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## 6QTS11OZ (Mar 27, 2005)

ftlfirefighter said:


> The overall diameter is .1" greater than stock. No rubbing with 8.5's f & r. I'm running 245/35-19 Michelin PS2's.


With those tires being directional, from the lower photo it look like their mounted backwards :confused . Are they? Or do the grooves fan out in the opposite direction on the inside?


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## 6QTS11OZ (Mar 27, 2005)

6QTS11OZ said:


> With those tires being directional, from the lower photo it look like their mounted backwards :confused . Are they? Or do the grooves fan out in the opposite direction on the inside?


*NEVER MIND!* They are directional but the grooves aren't of a V-pattern. My bad!


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