I am SHOCKED
 

nitto 555 245 wide tires fit on stock rims, no rubbing.

just FYI.

stock ride height?

stock ride height. but he said he had 4 people in the car driving and no rubbing. I don't know how fat these people were, but that could be like a .5 inch drop in the back...

im running 225's with a 1.5"drop and still have about a 10mm buffer so next time around ill be going to 235

you should be cutting it pretty close after that!

the 245s bulge out a little too much for my taste, but I am really surprised they fit in the wells at all. impressive.

Remember that different tires have different actual widths. The tire sizing itself is not enough to determine how wide the tire is going to be.

Here's some examples. In these examples, both tires are exactly the same 225/50/16.

http://www.3dluvr.com/crossbow/incom...e_sidewall.jpg

Note the sidewall on the two above tires. The one on the right bulges out, while the one on the left is flat.

http://www.3dluvr.com/crossbow/incoming/tire_widths.jpg

Here we have a 17x7 on a 215/50/17 vs a 16x8 on a 225/50/16. Note the massive difference in width. Technically it's only supposed to be 10mm wider! But due to the rim and tire change, its closer to 25mm wider per tire.

Actual tire width is determined by the tire manufacturer's sidewall reinforcement, tread and compound design, and the width of the rim the tire is being mounted on. More aggressive rubbers tend to have heavily reinforced sidewalls, which tend to stick out more then all-season grade rubber.

Additionally there seems to be some sort of craze where people put on wider tires then they should be on not wide enough rims.

Most of the people running 245's should be running them on 8.5 inch wide rims. (a 255 probably needs a 8.5 minimum, and a 9 inch wide recommended) If you don't use the proper rim sizing, you lose sidewall reinforcement, and hurt the ability of the shoulder to wear and be reinforced properly in a turn. This causes flex, which in turn causes worse handling.

Reference
Mazda6Tech - Wheel and Tire Fitment Guide

mazda6techowned lol

1. neither of those pictures worked
2. I know that, and that is why I put the brand and the model
3. ford puts (or at least did on the mustang one of our techs has) 245 tires on 8" wide wheels from the factory, and factories are usually reserved in how wide the tires are on their wheels
4. I don't think he is as much worried about wear or corner handling as he is straight line accelleration

1. Fixed.
2. Aye, I was just putting that information there for others.
3. The engineers at ford are incredibly smart. It's the penny pinchers and marketing departments that screw everything up. Did you know that the stock tires on a mazdaspeed6 don't even have the proper load rating for the car? Many tire selection choices have little to do with performance and everything to do with kickbacks.
4. Ya which is sad :(. You can have the best of both worlds with proper selection.

I like to use toyo's guide for rim widths. It's easy to get to.
http://marktg.toyotires.com/file/18966.pdf

The center of the 3 rim sizes is the one you want. Minimum size will give you sloppy sidewalls. (Like trying to put a 235 on a 7 inch rim).

yeah I was looking at the bulge in his tire and telling him there was no way he was going to be able to curb his rims with those things on there... another plus?

penny pinchers suck.

The widest you should go on the stock wheel is 225...since the stock 215s are slightly tapered. 245 on a 7" rim is looking for trouble; accident waiting to happen.

If you want 245 get yourself at least an 8" rim...still slightly too big for an 8" rim, but much safer than the stockers...

How do tire places sell these configurations...wouldn't they be liable if something happened?

Yeah, 235 on a 7.5 looks a tiny bit too much... 245 on 7" would be crazy lol. I MIGHT get 225/40 my next set of tires. Unless I get wider wheels or something.

he's one of our techs. he put them on himself.

also, why is it "dangerous?"

aren't the stock wheels 7.5 wide?

7, sadly

AH

well I'll feel much better about getting 8" wide wheels then. I was thinking it was only going to be a .5" step up.

They are liable. Technically they are supposed to tell you the sizing is wrong, and make you sign a waiver if you are determined to put too wide a wheel on too thin a rim. However since most of the tech's responsible for putting on tires/wheels are generally not very experienced, they tend to forget to do this.

I believe you waive all your rights when purchasing tires online (like tirerack), as part of the argument thing you have to click, as there is no way for them to know what your true application is.

It's not so much dangerous as negative in performance. When you get a wide tire on a thin rim, you get sloppy handling. The tire is too far away from the rim to get shoulder reinforcement, so when you turn, the shoulder tends to flop back over on itself, causing excessive wear and poor handling. Of course if you go far too wide (out of spec) there is always the chance that the tire can separate from the rim...that's when it gets dangerous!

I used to have a great photo of this. I'll try to find it.

I'll agree that you receive diminished performance, but I seriously doubt that it creates a "dangerous" condition.

If you take a corner too fast you can break the seal off the rim resulting in a blow-out, then you're out of control...

I've seen it in autocross races...even with near stock sizes with low tire pressures... But an oversized tire will experience this condition regardless.

Not dangerous in straight lines...but I wouldn't take any twisties...

Oh, in addition, you can also ride on the sidewall, which has no traction...push straight into a corner.

he's not autoxing. he's just driving around town. and maybe the drag strip. I find it hard to believe that with all of the force keeping the bead on, you could bust a bead on an oversized tire. undersized, maybe. with a too big tire, there is even more force keeping that bead seated. he's also not running low tire pressure like in autox. in conclusion, this is not a valid comparison.

Well, i have 8 inch wheels and definitely want 245's... Nitto 555's are shit tires though, bleh. I didnt like them at all on my Cobra. They are very loud.

plus, evidently, they're smaller tires. or something. cause I thought 245s would rub like a mfer.

The bead busts because of too much sidewall flexure... It eventually pulls the bead off enough to create a quick air leak resulting in a blow-out/instantly flat.
If he is just driving around town, I guess its OK...

But I personally wouldn't do it...I'm a performance freak anyway.:crazy:

I guess its a moot point. The general consensus is that its not recommended/ideal.

I agree that it isnt, but it kind of looks pretty bad ass. it bulges just a tiny bit too much for my taste, but it's not my car, so to each his own.

You guys don't think 235/40 on a 7.5 wide is too excessive do you?

I don't think it's too wide at all.

when I get wheels/tires, I think I might try 245s on an 8" wheel. I think that would be just about perfect.

Yeah, widest that's RECOMMENDED for 7.5 is 225. I think it's 235 for 8". But w/ 245s on a 8" then you'd pretty much be in the same boat as me (would be fine)

10 mm is 1/3 of an inch about (ok a little more). so yeah just about the same boat.

Here's some 245/45/16's on 16x8 rx7's.
http://www.glue.umd.edu/~greghess/kook/kook5.jpg

(What I used to run on my 6)

One thing you really have to watch (in terms of handling) is how your rear and front suspension is setup when you start going really wide. The MS3 is lighter then my 6s was, and that car was AWFUL with 245's on it (in terms of handling) until I modified the suspension.

Basically with 245's on the car, with stock rear suspension, the rear tires will practically never reach proper operating temperature...they just aren't being used. The fronts by comparison, are being beat the hell outta of. (This is one of the arguments for a REVERSE staggered setup). Stock, those wide rears gave unpredictable handling, and never let go, promoting heaploads of understeer.

When I threw on a massive rear sway bar, the car came to life. It was incredible. With the rear suspension stiffening up, and allowing the rear tires to be utilized more, the handling was awe inspiring. Even some local club racers had a blast tossing the car around.

that's pretty wicket looking. it's just depressing to me talking about these tiny tire sizes as being too big. when I had my Z, 245s was the standard that we went for on the front, and 275s on the rear. that was standard. there were guys running 305s on the rear. I'm not used to this kind of tire sizing, but I'm pretty sticky with stock rubber, so I guess each car calls for different things.

Well here we are limited by fitments. Those front struts are one major issue...(coilovers provide some additional space) and though you can fit wider tires in the rear, it provides only negatives, no benefits (besides cosmetic or aesthetic).

You also start running into issues when you go excessively wide in terms of handling. There is a sweet spot for every car. Of course all these rules change if you are only concerned with straight line handling (having slicks stick out in the front is not a big issue then), but I always see the car as a handling/road course monster first, and a straight liner second, so I'll always be part of the handling over raw speed crowd.

You could always get custom wheels from fiske, in perfect offsets and try to run some 255's on 17x9's or 17x8.5 (or whatever size you want), but that can get really expensive really fast.

Did you ever read the 350Z articles on restoring the vehicles handling by taking our the wider rear tires and running the same size all around? Interesting stuff!

I got my Z right when that craze hit actually in 2004ish? you can (with the right wheels) fit 275s all the way around. it totally changes the plowing characteristics of the car though, and people were spinning on the track and smashing walls.

I always liked the wider in back look anyway.

Ya, thats the exact reason why factory dials in understeer. If you don't know how to recover from a slide, you'll go spinning...and unfortuantly, most people don't know when to stop trying to correct, and just let the car go.

If you correct, fail, and try to correct again, you usually end up spinning in the opposite direction, where there is less runoff, and hard barriers instead of soft ones. Thats why track instructions will usually tell you to NOT try and correct, and just both feet in, and hang on. Most good tracks have runoff on the planned off track. I watched a Porsche GT (500k car) smash into a wall from an overcorrection...if they had just put both feet in, they would have just runoff into the wide open clearing with no wall.. :(

yes, as well as most people's initial reaction if the back comes a little loose is to at least let off the gas, if not hit the brakes. that's the worst thing you can do.

Exactly. Hitting the brakes or lifting, causes a weight shift from the rear to the front, putting more grip on the front, and less on the rear, increasing the oversteer, and making the loss of control even worse, or unrecoverable. (I know you know this, just stating it for others reading the thread).

trust me if there's a curb there is a way...

So you think an adjustable swaybar is better the coil overs for those larger tires? Whixch 245's did you go with?

I have 18X8s with a 45 offset. I have Cobb lowering springs. Is there a possibility of fitting 245s to this setup without issues? 235s maybe? I am currently running 225s with no issues and when it comes tire time, I would love to stuff some 245s under my ride.

Coilovers actually increased the understeer on my 6. The front rates were higher then the rears. (Almost all coilovers are like this). I think I had 13 kg front and 9 kg/mm rear. It wasn't until I threw on a freaking massive RSB that the car finally got tail happy, and I could lift/tuck around the bends. (Very very controllably).

I'm actually planning on just doing a Racing beat RSB on the MS3 and seeing how the car handles it, before jumping head first into the whole coilover game.

The trick is to end up with a neutrally balanced car, that you can easily weight shift one way or another, with minimal lift/roll.

Those were hankook Z212 Ventus 245/45/16. They were great. Wonderful dual duty tire (street/track). Also good wet weather performance.

They aren't as hard as RT615's (better dry better lateral), or as straight line grippy as RE070's, but they're quieter, and handle the rain better. Also pretty inexpensvie for what you get. I have no qualms recommending them for a good street tire that doubles as a track one.

(I'm running RT615's right now btw).

I just measured the MS3 rear bar and it is already 27mm, same as the rear bar that Racing Beat sells for the Mazda 3, save your $153. Have you noticed how easily the MS3 picks up a rear wheel turning into a slope driveway? The rear roll stiffness is already maxed IMHO. Weight distribution is the handling problem with this car.
-enganear

Yes I have noticed, but I have yet to jack up the rear and check it out. (Only done oil changes thus far, and some minor engine stuff). Thanks for saving me 153 dollars :). I guess the only real options would be the cobb or hotkious? (Man I can't spell that for the life of me).

And yes I've noticed the Tripod effect. Have you noticed any improvements with the dsc off in terms of "tuck" in?

With my 18x8 SSR's at 48off and stock suspension, I rubbed the rear driver side top fender with 225/45/18. I have since rolled the fenders and plan on changing sizes to 245/40's when the SO3's are done. In addition I have the rear Cobb sway installed and received the Cobb springs awaiting their turn to be put on.

While I have enjoyed the Bridgestone SO3(discontinued) and have heard great things about the Pole Position RE50A's my next tire purchase will be Advan Neova's if I can find them in that size.