FFRGTM

It's really not as simple are you guys are making it. When you go with a wider tire the contact patch become fatter and shorter. You will have increased lateral holding with decreased longitudinal holding. It's similar to the reason that top fuel dragsters have huge tires than wrinkle and create very very long contact patches.

When you put on different tires, you are changing the SHAPE of the contact patch. Not to mention the fact that wider tires will most likely have a higher spring rate (which is in series with the actual springs on the car... not including any bushings) and a much lower slip angle.

To be honest, without testing you should NOT be moving too far away from stock tire sizes. It's not like automotive engineers just pick random numbers, all of the suspension geometry, roll stiffness, damping, and s-awc algorithms are optimized specifically for the oem tires size and construction.

Toxin

iTrader: (2)

Interesting thought. Most people on here just slap 275's on without giving it much thought.

hotdog

iTrader: (4)

Well, there's also the question of "Is it worth it for what I use the car for". That's a separate question than "Is there a performance gain", mind you.

dboz

iTrader: (1)

There is some thought to the fact that a wider contact patch can also tend to act like a snow shoe so to speak. You disperse the weight of the car over the wider patch and have actually decreased the PSI pressure which in certain conditions could actually cause a loss of adhesion? Just something to think about. I have never seen tests, but that is why you typically like skinny tires for snows.

raytrix

iTrader: (12)

what about 255/40 on 18x10 rims

goofygrin

iTrader: (5)

holy crap you just bumped a 4-5 month old thread to post some worthless crap?

The reason our car comes with 245 wide tires is bean counters, accountants. A 245 wide tire is much cheaper than a 265 tire (ask anyone that's bought them). That's it. I bet if you asked the mitsu engineers that they'd say they wanted a wider tire. Have you actually looked at the amount of room in your wheel well? You can fit MONSTER tires in there without any fender work. That's no accident.

A wider tire on the X is faster, plain and simple. The X has a huge amount of mass and the small contact patch given by a 245 is simply too small to deal with that heft when pushing the car. The result is overheated, shredded tires. You can argue all you want about some mythical engineer's desires and top fuel dragsters but you'll be dead *** wrong in this case.

Don't believe me? Go ask anyone in STU whether they'd rather stay with the 245 wide tire or whether they'd move up to a wider tire if it was legal. Or go take a look at the C6 Z06's at the track on slicks. The really fast ones have 315's up front. The slower ones are running 295's up front.

Urbn Asslt Vhcl

I disagree, cost of tire changes from brand to brand and Advans cost a lot more then say Kumhos. So just because their wider does not make them more expensive. Also to note is that sometimes wider tires will weight more but that can very by brand and model as well. Tire weights are becoming heavier then wheel weights now and if you take 2 of the same brand and model of tire with sizes going from 245/40/18 to 265/40/18 you'll get a slightly heavier tire, a taller side wall and a larger overall diameter. If you take all that into consideration you'll probably loss performance and fuel economy. Now if you throw in changing wheels sizes and offsets even more variables are added. Their is lots of engineering and testing that goes into wheel/tire sizes then just throwing something on because it's cheap, picking the right gearing is another factor to.

Just my 2c

jackygor

iTrader: (9)

Wider tires should, in theory, take more heat and dispense it faster than narrow tires. There IS a reason why Gate's evo x is running 275/35/18 instead of 245/40/18, assuming the argument here is for absolute performance. I am with goofy on this one, Mitsubishi obviously cheaped out on the tires, or else why would they spend the extra money and R&D to make the Evo's wheel well that wide?

vboy425

iTrader: (19)

the tighter the salom is the smaller the tires you should run. Vice versa with bigger tires. Bigger tires and tighter turns actually slow you down more than anything.

FFRGTM

I am not saying a 245 is faster than a 275.. i'm saying that because our car came with 245 tires, it was optimized for those tires... nice reading comprehension. Also, please try reading a god damn book on vehicle dynamics... I'm not making up some mythical bull****, this stuff has been concrete for years and years.

Unless you somehow know more than the engineers at Mitsibishi don't go changing a bunch of **** on the car because it doesn't look like your favorite car in tokyo drift... try applying some science. You are after all piloting a 3300lb steel and plastic box around.

FFRGTM

I agree with everything you said... while this obviously does not apply to a heavy car like the evo, it's still good to keep in mind that with ultra lightweight cars there is a limit to how wide you can go before the performance starts to drop off unless you're running insane levels of downforce. Still... this is not what I'm saying.


Just a recap: mistu engineers did not optimize the geometry, spring rates, damping rates, sway bar rates, s-awc algorithm ect. for some imaginary tire that COULD fit in the wheel well. They optimized everything for what comes on the car worldwide.

I said you shouldn't move too far away from the 245s WITHOUT TESTING which involved optimizing the car for the new WIDER tires.

Most of all the wider tires are going to have smaller slip angles which the ASC, center diff locking, and AYC are not programmed to handle... not to mention the designed toe change in compression and droop. Yes, the OEM will design bumpsteer into the car ON PURPOSE to help avoid situations like trailing throttle oversteer.

goofygrin

iTrader: (5)

so how much testing have YOU done? How much track time do YOU have to support your theory?

I come from the school of actual performance not just reading out of a book.

Book learning is great and all but I live in the real world where your fancy book learning can leave you scratching your head when something doesn't work like you expect it to.

I 100% guarantee that the COST was likely the number 1 goal when designing the Evo. There are simply too many cheap *** parts on the car for it not to be. Look at the UICP? Seriously? The tire and wheel was decided by the accountant and then the engineers made it work.

You're trying to scare people away from running a wider tire... to what end? The car handles SIGNIFICANTLY better with a wider tire on it. In my opinion being able to avoid the accident >>>>> lessening the accident.

EvoG8r

iTrader: (31)

I think what Goofy is saying is that he has real world testing that helped him run faster times in autocross. Most guys who race their cars will tell you to go wider then stock on an Evo.

FFRGTM's take away to me is not to just throw a bunch of **** on the car and expect it to drive better. You need to do research and make adjustments upon real world testing.

Example; throwing a set of Ebay 2" lowering springs and some Tenzo 19x9.5 30lb wheels with some Nexxan all seasons at 265 width will not give you a superior handling machine. You've all seen that ricer in your town.

Both of you make a point. Less fighting and more discussion and collaboration.

jackygor

iTrader: (9)

Haha werds, I think the argument here is assuming you have lighter wheels and gripper tires, all while it is lighter than the OEM setup, and I know this can be done!

Hiboost

iTrader: (9)

I plan on doing some skidpad comparisons with my friend's stock Evo X. Basically compare his stock suspension and tires and see what actualy lateral G's we measure as compared to the documented .99g that the car is supposed to have. With that baseline we'll see how 275/30-19 tires on 19x9.5"wheels compare with a Coilover suspension. If there is time I'll also get data points with the wheels and tires swapped so he'll test stock car with my wheels and I'll test coilovers with stock wheels. Should be interesting if we can get accurate and consistant enough with testing.

I can pretty much tell you that my combo will out handle the stock setup, it's just a matter of how much though. I know I have plenty of power to make use of the wider tires on corner exits under power and since I didn't go with an aggressive offset the tires will be close to stock location as you could make them.