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The theory and myth to date was that going even as low as +42 in offset, a Mazda6 owner could avoid fender rolling by going with a 215 width tire. Truth be told, I helped propagate this rumor because my previous set-up, 18x7.5" +42 ALT AT-296 Blades coupled to 215/40/18 Nitto NeoGen ZR NEVER rubbed EVER, not even close, no matter what the weight load in my Eibach lowered 6. As I later grew to accept though, 215/40 is way off the track of ideal or safe fitment options we should consider due to the inherent wheel+tire diameter and featured load index. So following theory, 215/45 should have be the next logical choice. The tire width is theoretically the same, and all that is increasing is sidewall height. Moreover, 215/45 is the tire size now used as OEM by Mazda for the 18" option, and the exact tire I am using is actually OEM on the new MS6. Adding everything up, I thought I had my solution to avoiding fender-rolling for low offset 18" applications :nana:.

Say it ain't so :tear:. This past weekend I finally decided to test out my combination of 18x7.5" offset +42 wheels coupled to 215/45/18 Bridgestone Potenza RE050A XL tires. I went to a parking garage at my work to mount them up because it was looking as though it may rain and I wanted to err on the safe (dry) side. Quickly, after mounting the rears, I thought to myself, "Man, this is close but I think it will be alright." I threw the OEM's into the trunk and rear seats, and got ready for the 2-3 mile drive home. This added what about 160-170 lbs. to the rear of the car itself? Still, I thought it would be OK and had just enough clearance :slap:. No sooner had I driven up the ramp of the garage then I heard the tell-tale sound :eek:. It wasn't scrubbing all the time, only when I took a turn at over 10mph :sarc:, and even then it wasn't scribbing terribly bad. Still, I consider any amount of scrubbing terrible in general. Let's just say I drove home very cautiously :(. Once home, I unloaded the OEM's and decided to take her for another test spin as a measure to see whether the lightened load would prevent the scrub. No luck there either really :unsure:. Scrubbing was less consistent and in fact non-existent in the straight, but if I took a turn at greater than 20-30mph then rest assured the tires let me know.

SO, moral of the story is, theories are just that...theoretical. As far as +42 offsets and allowable 18" fitments go, I contest there is officially no way to avoid fender rolling :nono:. After all this time spent figuring a way to avoid fender rolling at all costs, I will now be fender rolling as soon as possible. I, dejected, put the OEM's back on to avoid any undue damage to my tires or wheel wells more importantly (both were safe and unharmed upon inspection). The one saving grace to the whole matter is I really like the way my ALT X-Factors looked while it lasted :p.

 

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"...So following theory, 215/45 should have be the next logical choice. The tire width is theoretically the same, and all that is increasing is sidewall height"

I found that the mfg's tire width (215) is a ball park number. They keep a tighter tolerance on section height for consistent diameters. You can check mfg's web sites or tirerack for more accurate widths.

rx7 example: on 16x8 wheels, I have goodrich 225-50 steet tires, and kuhmo 245-45 track tires.

the 225's (8.86") measured at 9.75", almost 25mm over the 225 value.

the 245's (9.65") measured at 9.13" , much narrower, and less than spec.
 

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Sounds to me that if we want to do 18" and +42 offset or greater then fender rolling is a must. This is a bummer considering my buddy just stuffed 20" Foose wheels onto his 05' lancer with minimal rubbing only while in reverse & obviously turning. :swearin: I know it sounds rediculous (20's on a lancer) but I must say it looks bad azz. The only 20's I saw on a 6 looked weetoddid. Oh well chalk it up to savin some greenbacks! ;)
 

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anyone could have told you that a 42 offset wheel would rub, you kidding me? you thought they wouldnt rub mebbe without a fender roll? jeez bro. thats pretty dumb, if you ask me.
 

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Discussion Starter #7
anyone could have told you that a 42 offset wheel would rub, you kidding me? you thought they wouldnt rub mebbe without a fender roll? jeez bro. thats pretty dumb, if you ask me.
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If you read my full post you would note that for roughly 18 months I was running 18x7.5 +42 offset wheels and NEVER rubbed no matter what the situation. So NO it is not completely "pretty dumb." I am not the only one that has "successfully" done this either as few other 6 owners have used this combo w/o rolling fenders. That list at least included past member 00000 (a.k.a. Lord of the Rims). The problem is that in order to do this, you combo'd with 215 series tires; in mine and his case we used 215/40. This was widely known across the board. If you follow this link and scroll or sort through, you will come across more than a few instances of this fitment sans fender roll.

http://forum.mazda6club.com/index.php?showtopic=16108

HOWEVER, to this day no 215/40 tire has the recommend load index for the 6 and the inherent wheel+tire diameter exceeds the 2% rule (too small). Still, this was better than fender rolling to some so it was lived with. Then 215/45's came along. Keep in mind, 215/45 is a practically brand new tire size. When the 6 came out in '03, I dont' think there were are any tires this size if so very few, moreover if they were available they were and still are damn expensive by and large. So it came to thinking, not just my own, that 215/45 should be able to get away w/o fender roll as well considering sidewall height is "theoretically" the main thing increasing or changing. Most didn't figure sidewall height would be too large a factor given the case that no one, including me, was close to rubbing with 215/40 again no matter what the weight load in the vehicle. Even with the springs compressed, the wheels would tuck nicley inside the lip with a bit of room to spare. Anyway, even current guru's like toyoguy thought it may work w/o fender roll, though no one was sure because no one had tried it out before. There are numerous posts bringing this question to mind with no firm answer; though, again, many thought it WOULD NOT rub.

Hence, me the guniea pig, willing to give it a whirl, to add truth or finally dispell the rumor. I contest MYTH BUSTED!!!! I was definitely :eek:wned: :bowdown:. I will be rolling my fenders as soon as I can either get my hands on a fender-roller or I find a reputable shop in my area. No harm no foul. I was going with this combo regardless and so all I lost was my time and energy. So is life :nopity:.
 

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alright then. i got OWNED. :)


anyway, why did you guys try soo hard to do it without rolling fenders? its not like a fender roll is completely scary or anything...
 

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I r nub.

Someone please link me to a good explanation of fender rolling. It sounds like you're talking about sort of folding the edge of the fender out so as to make more room for the tire, is that it? Wouldn't the tire still rub the wheel well on the inside?

And regarding the 215/45/18s, I have to believe they'd fit and not rub on a non-lowered 6, no?

And by the way, this was a beautiful post. Very informative and relevant, will no doubt save several people some cash and disappointment. Kudos for you! :thumbup:
 

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Discussion Starter #10
I r nub.

Someone please link me to a good explanation of fender rolling. It sounds like you're talking about sort of folding the edge of the fender out so as to make more room for the tire, is that it? Wouldn't the tire still rub the wheel well on the inside?

And regarding the 215/45/18s, I have to believe they'd fit and not rub on a non-lowered 6, no?

And by the way, this was a beautiful post. Very informative and relevant, will no doubt save several people some cash and disappointment. Kudos for you! :thumbup:
[/b]
Thanks for the "props." I wish there were better ways to earn props then failed ideas, but you win some you lose some as they say. Anyway, your idea (description) of fender rolling is dead-on, but when the lip is rolled properly you end up with about 0.5" of extra clearance. As you could check for yourself, lip of the rear wheel well is like this on the drivers side L and mirror image (backwards capital L) on the passender side. When you "roll the fender" you are pushing the horizontal part of the L ( _ ) more to the vertical ( l ). In the end, it takes more the shape l/ if not pushed full vertical even. This explanation may or may not be sh!tty for you. In any case, follow this for a better and case-n-point explanation.

http://www.mazda6tech.com/index.php?option...&id=17&Itemid=1
 

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Discussion Starter #11
alright then. i got OWNED. :)
anyway, why did you guys try soo hard to do it without rolling fenders? its not like a fender roll is completely scary or anything...
[/b]
For me it has really been 2 things. 1) Access to the proper fender rolling tool 2) FEAR!! :unsure: Though there are numerous body-shops in my area, none of them I really trust enough not to somehow screw me over with workmanship or in the pocket. Everything in my small slice of suburbia (central VA) seems to cost more than it would for any of my friends circa my old stomping grounds (Southeastern PA just outside Philly). Though I make it up there to visit my folks semi-regularly, getting work done on my car is seldom the focus. Regardless, I know I could rent the tool, but back when I was first considering aftermarket wheels, the waiting list on that thing was already so deep. I would have had to wait a year (exaggerating) but still it looked like 4 months best bet. If anything, I am a highly impatient patient person :sarc:.

Then came FEAR!! Whether misguided, misinformed, or ignorant, I have always been anti bending the METAL of my car for my own vain or assenine purpose. Let's face it, most of here are trying to convert are car away from ideal the manufacturer intended, whether it be looks or performance. It is one thing to put aftermarket wheels on to that aim (simple), it is another thing to permanently physically adjust your car to make it work (hard). All my modifications have always been fully reversible, and I could always revert to OEM. There is no return from fender rolling. I have always been weary of whatever damage it could do (paint damage, metal damage, etc.). I now realize that as long as the right tools are used for the job (roller and heat-gun) that no harm should become of it. Thanks to all of you, who were my own fender-rolling guinea pigs :p.

Still, I am back to access issues. To this end, I am hoping the proposed April or May Mid-Atlantic Install/Fender Roll meet will come together. If not, I am already researching my local alternatives if not just biting the bullet on the fender tool rental myself. I REFUSE to use the baseball-bat, pvc pipe, etc. technique though. All-in-all, more money I was hoping I could either avoid spending or spend on something else for the 6.
 

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Anyway, even current guru's like toyoguy thought it may work w/o fender roll[/b]
Where did I write that? I don't recall ever saying a +42 would or could work without a fender roll. Hell, I went +48 b/c I was too chicken to do +45! I don't want my fenders rolled, either. :nono:

I'm not really a wheel guru, and I tend to stay away from threads about which wheels will work unless I'm very certain about the answer. But I do know about tires! :yesnod:
 

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Perhaps ToyoGuy can help me out here...

But section width (the first number in a tire size) is NOT the tread width, which is probably what Kevink2 was measuring. SECTION width is the width of the tire at it's widest point, which is most times NOT the contact patch. Typically that is measured between the middle of the two sidewalls. And different manufaturers (and very different types and styles) will have VERY different tread-widths, depending also on the width of the tire compared to the width of the wheel.
 

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Perhaps ToyoGuy can help me out here...

But section width (the first number in a tire size) is NOT the tread width, which is probably what Kevink2 was measuring. SECTION width is the width of the tire at it's widest point, which is most times NOT the contact patch. Typically that is measured between the middle of the two sidewalls. And different manufaturers (and very different types and styles) will have VERY different tread-widths, depending also on the width of the tire compared to the width of the wheel.
[/b]
That's correct. And a 225-width tire isn't going to be exactly 225 mm. There is a range of acceptable tolerances, so a Toyo 225 might be wider or narrower than a Pirelli 225, for example. And it may differ among sizes even within the same manufacturer. For example:

Toyo Proxes 4 225/50R16 is 9.1 inches wide on a 7.0 inch wide wheel, but

Toyo Proxes 4 225/45R17 is 8.7 inches wide on a 7.0 inch wide wheel and

Toyo Proxes 4 225/35R19 is 8.7 inches wide on a 7.5 inch wide wheel!

Go figure!
 

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Kid,

I really wouldnt be THAT worried about rolling your fender. With the temperature the way its been and a heat gun here in VA, I wouldnt worry about paint chipping or anything.

Also my general advice to people is I suggest a roll with +45 on a 7.5 inch rim with 225 tires. Like TG said, not all 225 series tires are the same exact width so there is a very very blurry line to guesstimating wether a roll is necessary or not. Unless the combo has been used already, there is no real way of knowing 100% with the borderline combos.
 

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Perhaps ToyoGuy can help me out here...

But section width (the first number in a tire size) is NOT the tread width, which is probably what Kevink2 was measuring.....[/b]
I was measuring section width (max width of tire ... ie rub factor), not tread width, which was wider on the track tires that had the narrow section width.

Thats why just saying a 225-xx-xx tire will not rub is misleading, as 225 can reflect a wide range of section widths, depending on brand.

----------

In general, tread width decreases as aspect ratio increases, for a given nominal ( ie named or graded) section width. A 225-16 70 series will have much narrower tread width than a 225-16 40 series tire.
 

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Discussion Starter #17
Kid,

I really wouldnt be THAT worried about rolling your fender. With the temperature the way its been and a heat gun here in VA, I wouldnt worry about paint chipping or anything.
[/b]
Thanks Philter25. I will PM you the same, but do you know what is going on with the proposed Mid-Atlantic Install/Fender Roll meet? I know the 8th and 15th (April) were two of the initially proposed dates, but things still seem uncertain for either day. Come to find out, I likely couldn't make either anyway because it just popped up that I have to go to up to PA the weekend of the 8th and then the 15th I have things going on here in VA. Pretty much, my entire April is accounted for already. I have called the shops in my area and none so far have a clue what fender rolling is or the one's that do don't have the proper tools to do this "custom work." I am already running out of quick options unless I wait it out on the rental, but still I would prefer not to do this myself having such little experience in the area.
 

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Hello, i was wondering if your mazda 6 is lowered ? Or stock ? I just bought rims 18x7.5 42 offset and i want to get 215 45 r18 to not rub . is that possible? What are your experience
 
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