Aggressive Wheel Fitment Thread
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OMGITM!
iTrader: (15)
Joined: Jan 2006
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From: Sunny Southern California
Nice work Chad, love the authentic MS kit 
Anyone care to guess specs? Doesn't count if I told you, I think I may have told a couple people. Square setup. Whoever guesses right gets a cookie
Anyone care to guess specs? Doesn't count if I told you, I think I may have told a couple people. Square setup. Whoever guesses right gets a cookie
Well an 18 x 10.5 +43 fits with a 285/30 tire
Putting a 10.5" wide low offset wheel on with a 245 tire just so the wheel lip can stick outside the fender is not only pointless, the car with the 285 will drive circles around you all else being equal
Putting a 10.5" wide low offset wheel on with a 245 tire just so the wheel lip can stick outside the fender is not only pointless, the car with the 285 will drive circles around you all else being equal
A 10" wide wheel is the max width you can use that sticks close to the factory offset and takes advantage of all the inboard wheel space @ 50 - 52mm offset. With a fat tire (285 or 295) it will fill out the fender and also look mean as hell with all that rubber under there. You also aren't going to experience handling and driveability issues that result from wheel offsets lower than factory.
If you want to run wider than 10" then you have no choice but to start lowering the offset because there is no more inboard space available without extreme mods like tubbing and major suspension relocation/redesign. With every width increment above a 10" width @ +50-52mm offset you'd have to move the offset out by half that amount.
So for 1/2" increase above 10" width (10.5") half that amount is 1/4" = 6.3mm or 7mm for practical purposes. At each 1.5" increase you could subtract 1mm to account for the fractions adding up to a whole number, but there aren't too many RX8s using 11.5" wide wheels let alone 13" wide, lol. At anything past 10.5" wide using this basis the fender will need pulling or flaring for an equally wide tire not to rub because it will be sticking too far outboard of the factory fender lip to clear. So the resulting size/offsets would be:
10.0" @ +50 to +52mm
10.5" @ +43 to +45mm
11.0" @ +36 to +38mm
11.5" @ +30 to +32mm
12.0" @ +23 to +25mm
Otherwise running undersize tires to accomplish this fails on several accounts. To make the tire sidewall lean for fender clearance means that it has to lean both on the inside and the outside. A ridiculously narrow tire is required the further outboard the wheel lip sits outside the fender lip. Way back when tire sidewalls lacked good support but todays performance tires are designed such that a wheel wider than the tread width/contact patch width accomplishes no performance benefit. So a wide wheel with a high positive offset just to put a skiny tire on it is pointless and silly. Some wheel width/tire size reference points are:
9" wheel @ 245 to 255 tire
10" wheel @ 275/285 tire
11" wheel @ 305/315 tire
12" wheel @ 335 tire
Some change in offset from the original +50mm (S1 models) is not going to have much impact, but as you continue to push it out the resulting scrub radius moment arm is creating a force that makes the tires want to turn out, putting the steering components in constant tension while driving in a straight line. As such a setup encounters uneven pavement, bumps, water puddles etc. that moment arm is going to try and rip the steering wheel out of your hand position. Even moreso for these conditions under braking because this same scrub radius moment arm is going to magnify the braking deceleration forces against the steering wheel as well.
So for me when I see someone running sub-10" wheels/tires with a high offset or otherwise not using the full inboard area of the available wheel well it is like people entering a body building contest. The wide wheel/narrow tire setup is like the skinn kid with smallish build puffing up and trying to look big and tough when in fact he is still just a silly looking runt to everyone who can see clearly. Leaving available space inboard is just like the person who has a big upper body with thin, skinny legs or vice versa. They simply are not fully developed. Ultimately it comes down to doing it right vs doing it wrong. Damn near everyone here is doing it wrong. What most of you are calling aggressive is the equivalent of carbon fiber vinyl applique wrapped over a steel part.
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Last edited by TeamRX8; Dec 24, 2011 at 11:31 AM.
Well it has to be posted somewhere and can always be linked/referenced, otherwise you can only lead the ignorant horse to the knowledge watering hole, but you can't force it to drink some common sense there.
Thanks Matt! I'm glad everythIng turned out the way it did. I just need to camber the front a little do I can lower the front a half inch to match the rear ride height of 11.5in 
can't go any lower without a pull 
Oh, my guess is 19x11 +23
can't go any lower without a pull Oh, my guess is 19x11 +23
Last edited by Chadwisk; Dec 24, 2011 at 12:09 PM.
![mike[piston eater]'s Avatar](https://www.rx8club.com/avatars/mike%5Bpiston-eater%5D-48728.gif?dateline=1334247180)
haha! Not quite. I was rubbing hardcore over bumps so I had to take them out. I do plan on zip tying them back on. I guess those pictures were cheating 
Here's some I just went outside and took in my driveway. Constructive criticism welcome, I am by no means a photographer. Just a man with a D50 that was given to me by a friend
These are raw images by the way, they haven't been edited at all. Another thing I need to start learning to do lol.
Here's some I just went outside and took in my driveway. Constructive criticism welcome, I am by no means a photographer. Just a man with a D50 that was given to me by a friend
These are raw images by the way, they haven't been edited at all. Another thing I need to start learning to do lol.
Haha that's max camber! That's not white paint on the left grill btw, it's water droplets. I just washed the car harharharhar. Reason you have to remove the side markers is because you have to remove the tab where the sidemarker bolt goes. When you turn it cuts the tire up and destroying the tire like that is not cool haha.
Even Ryan Gates Evo(around 750whp), one of the fastest cars in the country is only on 275s (AWD, but still).
I'm not sure why you guys take autocross so seriously.
18x10.5 +15 w/ 265s. Gates 311
Last edited by imput1234; Dec 24, 2011 at 08:20 PM.
