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tyranosaurs-WRX
02-18-2011, 09:05 AM
Im looking at a set of wheels, he says they are all 40 offset but the fronts are 225 tire and the rears are 245. I know nothing about what the offset means other than my stockers are 45. so any information, questions, comments, conserns. would be useful. thanks

Crispy
02-18-2011, 09:16 AM
http://www.tirerack.com/wheels/tech/techpage.jsp?techid=101&currentpage=90

Offset really doesn't tell us anything without knowing wheel size. Also do the tires have the same rolling circumference? I'm not sure you can get a 225 and a 245 closer than almost an inch different.

tyranosaurs-WRX
02-18-2011, 09:19 AM
they are all 17's, but I'll ask the wheel widths, if you go with the biggest tires possible you are right they would still be an inch bigger wheel in the back so it could be 17x7 in the front and 17x8 in the back.

Crispy
02-18-2011, 09:30 AM
You could be 17x8 all around, I'm talking about the difference in the circumference around the tire. The distance the tire travels as it makes one full turn. With our AWD you need to be pretty identical to avoid any possible issues with stress on the differentials.

You can use this link to compare tire sizes and see the differences.
http://www.miata.net/garage/tirecalc.html

Crispy
02-18-2011, 09:36 AM
With all that said, I'm not really sure what the definitive answer is on how close they have to be to identical. Maybe someone else can chime in that has more knowledge there. I think a few guys on here have looked at going staggered in the past, maybe someone else has real info on how close they need to be in size, or how appreciable the drivetrain stress would really be.

tyranosaurs-WRX
02-18-2011, 09:38 AM
I get you now, I misunderstood. and i now see the problem they are 225/45 and 245/45, so the rears would be bigger. thats annoying, I guess I will see if hell take the tires out of the price.

20sti05
02-18-2011, 12:43 PM
you can have a staggered wheel set up but they have to be the same size tire on all 4 wheels.

i just got 18x8.5 with a -48 offset. im going to get a 245 40 18 tire for them. tirerack.com shows that this size is really close to my factory tires. so it wont mess with the speedo. the 245 is how wide the tread is and the 40 is sidewall height. if i was you i would go same size wheel all the way around. but if you want that look...its 8) too.

NoAffiliationSTi
02-18-2011, 02:29 PM
[quote="20sti05"]you can have a staggered wheel set up but they have to be the same size tire on all 4 wheels.quote]

+1 this is correct, same tire size on the AWD otherwise you'll have hell to pay.

Staggered is a bit tougher setup on a AWD becuase its either a wider wheel in the rear or a taller and wider wheel in order to get that staggered look....once you find something finding a offset which works on a subaru is difficult as well.

btw offset is this: If you were to look at the width of the wheel and cut it exactly in half, that would be zero....if you move the mounting pad (the part that touches your rotor when you put the wheel on your car) toward the inside (or back) of the wheel that negative offset... if you move that pad to the outside (or front) of the wheel that is a positive offset

VF34RX
02-18-2011, 02:52 PM
Very rarely will you see negative offset for our cars. Our cars come with +50ish offset and a fairly aggressive setup is +38 or less.

dukenukem
02-18-2011, 03:13 PM
Here is a nice little link to see how a certain offset wheel is going to fit on your car.

http://www.1010tires.com/wheeloffsetcalculator.asp

tyranosaurs-WRX
02-18-2011, 03:52 PM
thanks mahir, that helps a lot. they would be perfect if it weren't for the rear tires being so much bigger. the 45 cross section of those moster 245 wide tires is 9.25 mm bigger diameter so a fair bit larger circumfrence, therefore my diff does not like.

VF34RX
02-18-2011, 03:58 PM
I would say if you kept the rolling distance (diameter) 0-2mm you would be ok. 3mm is 1/8" so i would think the diff could tolerate that or less.

Crispy
02-18-2011, 05:04 PM
I would say if you kept the rolling distance (diameter) 0-2mm you would be ok. 3mm is 1/8" so i would think the diff could tolerate that or less.
Rolling distance = circumference, so not sure which one you mean for sure. The number I've seen on NASIOC that someone supposedly pulled off my.subaru.com was 1/4" or less difference in circumference, I'm assuming this must have been in some technical bulletin or in a newer owners manual because it isn't in my manual anywhere.

VF34RX
02-18-2011, 05:11 PM
I would say if you kept the rolling distance (diameter) 0-2mm you would be ok. 3mm is 1/8" so i would think the diff could tolerate that or less.
Rolling distance = circumference, so not sure which one you mean for sure. The number I've seen on NASIOC that someone supposedly pulled off my.subaru.com was 1/4" or less difference in circumference, I'm assuming this must have been in some technical bulletin or in a newer owners manual because it isn't in my manual anywhere.

They go hand in hand. You can't change the diameter and not the circumference. But yes i heard it was 1/4" too but i wouldn't push it. If you go by that then it would be 6mm or less would work.

Crispy
02-18-2011, 05:44 PM
I would say if you kept the rolling distance (diameter) 0-2mm you would be ok. 3mm is 1/8" so i would think the diff could tolerate that or less.
Rolling distance = circumference, so not sure which one you mean for sure. The number I've seen on NASIOC that someone supposedly pulled off my.subaru.com was 1/4" or less difference in circumference, I'm assuming this must have been in some technical bulletin or in a newer owners manual because it isn't in my manual anywhere.

They go hand in hand. You can't change the diameter and not the circumference. But yes i heard it was 1/4" too but i wouldn't push it. If you go by that then it would be 6mm or less would work.
Right but changing the diameter 1/4" will change the circumference more like 3/4" so wasn't sure which you were referring to. I'm just going off of things I've heard and don't have any experience or definitive knowledge here so just trying to clarify and understand.

20sti05
02-18-2011, 06:32 PM
Very rarely will you see negative offset for our cars. Our cars come with +50ish offset and a fairly aggressive setup is +38 or less.

i didnt mean to put -offset :oops:

VF34RX
02-19-2011, 05:57 PM
Right but changing the diameter 1/4" will change the circumference more like 3/4" so wasn't sure which you were referring to. I'm just going off of things I've heard and don't have any experience or definitive knowledge here so just trying to clarify and understand.

We are both correct. I think it would be pretty cool to run a staggard setup imo.

kyNg02bugeye
03-23-2011, 05:49 AM
You guys and your weaksauce offsets.... 0 offset + 275/35-18's!

cseaman
03-23-2011, 06:28 AM
nice to see someone else talking about doing staggered. you guys are all on the right track. i did hours of research and found out that you can get away with 3-5mm difference, no sweat. the thing people have to remember is that just your stock front and rear tires can have that much of a difference just from wear after driving.

i personally will throw out that i think it's a complete waste of time and risk to run a 17x7/8 stagger. I was going to do 8.5/10. I don't even think you'd be able to tell a 7/8 was happening on a Subaru. Imprezas swallow up 8" wheels like it doesn't matter..and 7s in the front. Well, that's basically stock.

VF34RX
03-23-2011, 08:23 AM
nice to see someone else talking about doing staggered. you guys are all on the right track. i did hours of research and found out that you can get away with 3-5mm difference, no sweat. the thing people have to remember is that just your stock front and rear tires can have that much of a difference just from wear after driving.

i personally will throw out that i think it's a complete waste of time and risk to run a 17x7/8 stagger. I was going to do 8.5/10. I don't even think you'd be able to tell a 7/8 was happening on a Subaru. Imprezas swallow up 8" wheels like it doesn't matter..and 7s in the front. Well, that's basically stock.

I think a staggard setup would look pretty good on a subaru. Plus you would be the only one around here doing it. I think omar is the only one locally that has done this when he had that nice set of works.

NoAffiliationSTi
03-23-2011, 10:46 AM
I woulda done staggered but the wheels I want are discontinued and really hard to find... Axis Hero's... maybe I'll run across some one day.

kyNg02bugeye
03-23-2011, 10:43 PM
nice to see someone else talking about doing staggered. you guys are all on the right track. i did hours of research and found out that you can get away with 3-5mm difference, no sweat. the thing people have to remember is that just your stock front and rear tires can have that much of a difference just from wear after driving.

i personally will throw out that i think it's a complete waste of time and risk to run a 17x7/8 stagger. I was going to do 8.5/10. I don't even think you'd be able to tell a 7/8 was happening on a Subaru. Imprezas swallow up 8" wheels like it doesn't matter..and 7s in the front. Well, that's basically stock.

I think a staggard setup would look pretty good on a subaru. Plus you would be the only one around here doing it. I think omar is the only one locally that has done this when he had that nice set of works.

Indeed...

George uses the wheels as track rims I believe