My Fiero came with 255/40/17 on a 7" rim and they did not look good. The tire looks bad squeezed on like that and stuck out from the body. I sold those and went with 225s and am very happy with the look and fit.
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12:23 AM
iced_theater Member
Posts: 1755 From: Green River, Wyoming, United States Registered: Jun 2003
That's much too big for that size rim. I'm sorta surprised it fit on that wheel....I believe a 235 is the absolute maximum for a 7" wide rim, maybe not even that.
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12:44 AM
Racingman24 Member
Posts: 2304 From: Land of 10,000 Idiots Registered: Apr 2003
Hey James, do you remember seeing my car at Wheatstock? I was parked right next to you. I don't know if you took any pics of my car, but at the time I had 235-45 up front and 245-45 in the rear. Both my front and rear rims are 7" wide, and I did not think it looked funny at all. It might with the 40 series, I'm not sure, but with the 45's on there, it looked really good. Or at least I thought so.
I now have 225/45 up front and 235/45 in the rear, and I miss my 245's in the rear, they just seemed to fill up the fender well better. [Tires are free so I can't be too pickey. ]
Eric
------------------ Used is such a harsh term. . . I perfer "Previously obsessed over" ;)
88 4 cyl 5 speed: All show and no go 86 SE V-6 Turbo 4 speed: All go and no show for sale
Wait. . . Did I just say I can't wait to do more work on my Fiero?. . .what, am I retarded?
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01:13 AM
riley Member
Posts: 965 From: Saskatoon, SK, Canada Registered: Feb 2004
TECHNICALLY you can fit any width of tire on any width of rim.
REALITY you have to be able to deal with the aspect ratio (second set of numbers in the size) of the new tire. To get that wide of a tire on your 7" rim you will prolly need atleast a 55 series tire. If you increase both width and aspect ratio you will need to adjust or atlest know that your speedometer WILL read incorrectly. the first link will help you to know how this sort of thing. the second link will help you decide if the new rim will fit properly.
On the Michelin website, it says that their 255/40R17 requires an 8.5" wide rim.
Here is a good rule of thumb: The maximum tire width should be one-inch wider on each side of the rim. So for a 255mm (about 10") wide tire, the rim should be no less than 8" wide. Obviously, for a 7" rim you should go no larger than a 9" wide tire. Also, depending on the stiffness of the sidewall of the tire, the tire becomes harder and harder to mount as the tire width gets wider than the rim, and can damage the rim in the process. I hope this helps.
[This message has been edited by cyrus88 (edited 09-14-2004).]
Rule of thumb is measurement across the tire tread should be equal or close to equal to the rim width. ie/ 7" rim, tire tread should be 7" +/- a fraction.
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04:12 PM
nightonfire Member
Posts: 1015 From: San Diego, Ca. Registered: Feb 2004
well hopefully you are with the 225. going to wide on a rim is dangerous especially if you are an agressive driver. the wall will not be able to support it and on a turn it will have the same effect as if your tire was flat. the rim will roll and dismount from the tire and you can end up messing your self and some one else up. Looks must be balanced with perfromance. always get answers before you do something you dont know the people at the auto places dont know everything.
Rule of thumb is measurement across the tire tread should be equal or close to equal to the rim width. ie/ 7" rim, tire tread should be 7" +/- a fraction.
I would tend to think you'd want a little wider. Think about it. 7" is roughly 185 mm. Would you want that skinny of a tire on a 7" rim? I've got 205/50 on a 16x7" rim and it fits nicely. Any smaller, especially two sizes smaller, wouldn't look right, and I'm sure it would have problems being mounted. Not to mention handling would be affected, as well as tire wear.
BTW, I agree with some of the others stating that a 225 would be as wide as you want to go. If these were truck tires, sure you could go 255, but the aspect ratio would be more like 60 or 70. The smaller your aspect ratio gets, the closer your section width has to be to the width of the wheel.
------------------ 86 SE 4 spd - 86 GT auto - 86 SE auto oh yeah, and the 85 coupe parts car
[This message has been edited by sqoach (edited 09-30-2004).]
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06:54 PM
PFF
System Bot
rogergarrison Member
Posts: 49601 From: A Western Caribbean Island/ Columbus, Ohio Registered: Apr 99
Thats the way its alway been as far as i can remember. You want a tire with a 10" wide tire, you got 10" rims. the way it should set on the car is the outside edge of the tread (flat part, not if tread wraps around) should set even with the bead of the rim. That gives the sidewalls the designed amount of support they need. Too much wider and they are wider on the ground and like already said, easy to pop the already out of line bead off the rim. Too narrow and you only get a good solid tire patch on the sides of the tread with a low amount of grip in the center of it. You end up with bald cords on the edges with relatively untouched tread in the center almost like improper inflation.
Each tire manufacturer has this..... they differ slightly but for the most part are the same.
Tirerack has this info for just about every tire. When your looking at a tire click "specs" and it will give you the "measured" or "optimum" or "designed" width rim (ie: 7.0") and also the operating rim width range for that tire. (ie: 7.0" to 8.0")
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11:43 PM
Oct 1st, 2004
musicman_L7 Member
Posts: 1149 From: Defiance, Iowa 51527 Registered: Nov 2002
Do you remember Litespd's white GT? He has 17x7 rims, and is running 215/45-17s up front, and 235/45-17s in the rear. They look really good.
I have 17x7.5 rims, and have a set of 225/45-17s all the way around. They look great up front, but the rears look skinnier, even though they're the same size.
With your rims, I'd go with 235's or smaller.
------------------ Nic Email me at my PFF username @hotmail.com
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04:09 AM
kooljess Member
Posts: 1135 From: FIEROS WEST USA Registered: Jul 2004
I'm running with 17x7 front with 225/45/17 and 235/45/17 in the rear. That's probably the maximum you can go with 7" rims. I'd like to get Simmons Wheels (Australian made) but I'm still trying to talk myself into spending that much money on rims again. At least I know they will fit my car, and they will give you serial number in case you want to change it. It's a 3 piece rims. The ones I have on my Fiero now is ok, even though it would have been nice if I could have gotten 17x 8.5 for the rear. Oh well.
This is why I (and I know for a fact other older very knowledgeable members) don't post on here much.....
quote
Originally posted by Skybax:
17x7 rim... The "optimum" size is 215/45
The "largest" sizes allowed are...
225/45 205/40 215/40
You CAN put a larger size on, but it's foolish to do so.
If you want a larger size tire, use a larger rim that allows the size.
---
They have charts these days for applications like this.
Very specific... X tire can go on Y rim. Takes the guess work out of it.
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Each tire manufacturer has this..... they differ slightly but for the most part are the same.
Tirerack has this info for just about every tire. When your looking at a tire click "specs" and it will give you the "measured" or "optimum" or "designed" width rim (ie: 7.0") and also the operating rim width range for that tire. (ie: 7.0" to 8.0")
The posts that follow...
quote
running 17x7 rims..... and 235/45-17s in the rear..... They look really good.
With your rims, (17x7) I'd go with 235's or smaller.
quote
I'm running with 17x7..... 235/45/17 in the rear. That's probably the maximum you can go with 7" rims.
It's one thing to try and help or contribute, it's ok to share opinion, and try to steer people in the right direction. But when discussions become random posts, and people are just posting without reading, it becomes what's called the collective monolog..... everyones talking and nobody listening.
[This message has been edited by Skybax (edited 10-01-2004).]
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