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Old 01-02-2006, 01:27 PM   #1
saggy
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Default Why did Subaru subtract 1/2" from rims of WRX?

Why did Subaru decide to specify 6.5" wide rims for the WRX, when for years Imprezas were fitted with 16x7" wheels?

Why the decrease in width when this was the most powerful, sportiest car released in the States since the SVX?

Why go backwards(if this can be considered that) by fitting a smaller wheel? Is it because a 6.5" wide rim is the optimum size for the 205/55 R16 tire? Was it that much cheaper to specify a 6.5" wheel instead of a 7" wheel? Is there an endless supply of RE92s in 205/55 R16 that need to be used up?(It doesn't seem so with a price of $150.00 each at the Tirerack(r).) Doesn't the 16x7 oem wheel support the 205/55 R16 tire better than the 16x6.5 oem wheel?
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Old 01-02-2006, 01:50 PM   #2
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I would guess it was a combination of cost & better mileage.

Plus they knew most WRX owners would be purchasing aftermarket rims anyways.

Last edited by fliz; 01-02-2006 at 02:02 PM.
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Old 01-02-2006, 02:03 PM   #3
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i'll say cost too
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Old 01-02-2006, 03:59 PM   #4
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Quote:
Originally Posted by fliz
I would guess it was a combination of cost & better mileage.

Plus they knew most WRX owners would be purchasing aftermarket rims anyways.

One of the problems with aftermarket rims is that they don't come in the ideal offset(ET+55) for Subarus. From what I've seen at TireRack the closest is SSRs with ET50--still not ideal. I know that Prodrive wheels come in the correct offset(the ones that are Subaru specific). And 2004 OEM BBS wheels for the STi are the correct offset. But you can only pull those off a STi or purchase them from a Subaru for $700+ dollars each, or you can get them for half price from a recycler or remanufacturer.
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Old 01-02-2006, 06:25 PM   #5
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I think the better question is, why did the 98-01 RS come with STi/WRX wheels?
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Old 01-02-2006, 07:03 PM   #6
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Quote:
Originally Posted by saggy
One of the problems with aftermarket rims is that they don't come in the ideal offset(ET+55) for Subarus. From what I've seen at TireRack the closest is SSRs with ET50--still not ideal. I know that Prodrive wheels come in the correct offset(the ones that are Subaru specific). And 2004 OEM BBS wheels for the STi are the correct offset. But you can only pull those off a STi or purchase them from a Subaru for $700+ dollars each, or you can get them for half price from a recycler or remanufacturer.
If you get a wider rim (than the 6.5 offered) you do NOT want a ET55. Depending on width of the wheel 48-53 generally seems to be the ideal sizing for offset.
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Old 01-02-2006, 07:31 PM   #7
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Not true.

Legacy GT wheels are 17X7.0 and ET +55 and work GREAT on our cars.
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Old 01-02-2006, 11:58 PM   #8
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Quote:
Originally Posted by tora
If you get a wider rim (than the 6.5 offered) you do NOT want a ET55.
Ideal offset really doesn't change. Keeping the same offset keeps the center of the tire in the same point in relation to the suspension bits. For some reason, the idea has been spread around this forum that ideal offset needs to shift with wider wheels. It's just not true.

But as wheels get wider, space between the wheel and the strut starts to get tight, so reduced offsets become necessary in order to run wider wheels. My experience is with the older cars - I think perhaps the WRX Sedan struts are offset in a manner that creates more strut clearance, so the problem might not be as extreme with them.

_Jeff
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Old 01-03-2006, 12:29 AM   #9
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Quote:
Originally Posted by tora
If you get a wider rim (than the 6.5 offered) you do NOT want a ET55. Depending on width of the wheel 48-53 generally seems to be the ideal sizing for offset.
Shouldn't the offset ideally be ET55(for the WRX) no matter the rim width? I thought offset is measured from an imaginary line running down the center of the wheel--so it should be independent of rim width. If offset is measured with reference to a point on the outside of the wheel I could see the offset needing to change. With ET55 the wheel will rotate on it's center axis(or at least where Subaru engineers intended). With less offset the wheel will rotate around an axis that is not in the center of the wheel, creating a push, which is why people talk about some offsets being bad for your wheel bearings. I've come to the conclusion that the only reason to get the offset less than ET55 or ET53 is because the wheel manufacturers just don't make them that high, or because you have a clearance problem on the inside. AFAIK only Subarus need them and it probably doesn't make sense financially to make wheels for a niche market--unless your company is going to specialize in Subarus, like Prodrive.

Like the previous post said, thats why Legacy GT wheels work great, they have the ET55 offset we need on a WRX.

Please forgive me if I don't know what I'm talking about--I'm still a noobie.
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Old 01-03-2006, 12:33 AM   #10
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....the bastards wanted to give us crap.....and DID.

that's why
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Old 01-03-2006, 12:39 AM   #11
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Quote:
Originally Posted by Portly
Ideal offset really doesn't change. Keeping the same offset keeps the center of the tire in the same point in relation to the suspension bits. For some reason, the idea has been spread around this forum that ideal offset needs to shift with wider wheels. It's just not true.

But as wheels get wider, space between the wheel and the strut starts to get tight, so reduced offsets become necessary in order to run wider wheels. My experience is with the older cars - I think perhaps the WRX Sedan struts are offset in a manner that creates more strut clearance, so the problem might not be as extreme with them.

_Jeff
Exactly what I have been thinking.

This thread: Sticky Thread Sticky: The Offset Information Thread, had me all confused because it starts out stating offset is relative to rim width. So the deal is, is that most wheels out there are not ideal for a Subaru(unless they have offset of ET55 or ET53), there are just some that are close enough to not cause too much trouble?
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Old 01-03-2006, 01:30 AM   #12
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No, if you want to run a 255 wide tire you are not going to fit it on a 7 or 7.5 inch rim. Ideally you are going to want 8.5-9". Running something that wide with a 55 offset will interfere with pretty well any strut set-up I know of. So in that case a 55 offset is NOT ideal. If you put an aftermarket brake kit you will be very unlikely to find a wheel with a 53-55 offset that will fit. You will usually have to go with a wider (or larger diameter wheel) with a lower offset. Since I'd say the average shmo on this site does NOT have a stock car I would also say that the stock 55 offset wheel is not ideal for most applications. Also the difference between a 55 offset and a 48 is negligable as far as increased wear on ANY part of the car.
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Old 01-03-2006, 02:13 AM   #13
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Because SOA ****ing hates the enthusiast!
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Old 01-03-2006, 03:56 AM   #14
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Quote:
Originally Posted by MattDell
Because SOA ****ing hates the enthusiast!
Which explains the release of the WRX how?
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Old 01-03-2006, 08:00 AM   #15
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Quote:
Originally Posted by THAWA
I think the better question is, why did the 98-01 RS come with STi/WRX wheels?

That may also be an issue of cost. The wheels were already in circulation overseas, so why produce something new?

But when they wanted to release the new-age car in the US, I'm sure that a 16" version of the wheel they decided to use in Europe (remember it was the same wheel, just 17" instead) was the economical choice. And it likely just happened to translate to a 6.5" width.

One of those unfortunate coincidences, I think. I don't personally believe Subaru "removed" 0.5" to spite anyone.

=S2=
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Old 01-03-2006, 10:08 AM   #16
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Quote:
Originally Posted by Siper2
That may also be an issue of cost. The wheels were already in circulation overseas, so why produce something new?

But when they wanted to release the new-age car in the US, I'm sure that a 16" version of the wheel they decided to use in Europe (remember it was the same wheel, just 17" instead) was the economical choice. And it likely just happened to translate to a 6.5" width.

One of those unfortunate coincidences, I think. I don't personally believe Subaru "removed" 0.5" to spite anyone.

=S2=

...a lot of the japanese think americans are 'lamers' and don't need or want REAL high performance anything....we almost certainly wouldn't have got the STi here if Mitsu haddn't done the EVO here, first.
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Old 01-03-2006, 12:45 PM   #17
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Because the 6.5" width works fine with a 205/55 section tire while the 215/45 or 225/45 tires used with the 17" wheels work better with a 7.0" rim. They spec the wheel for the tire they install not for one that people would like to install. It also saved 1/2 pound per wheel over the previous 16x7 wheel which may have been important to them as the GD Impreza porked up a lot.
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Old 01-03-2006, 01:36 PM   #18
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Quote:
Originally Posted by tora
No, if you want to run a 255 wide tire you are not going to fit it on a 7 or 7.5 inch rim. <snip>
I addressed that in my prior post. 53-55 remains the IDEAL offset regardless of rim width. Problem is, it doesn't fit with wide wheels. So you reduce the offset. This does not make the reduced-offset ideal, it just is the compromise which you're forced into if you need to run wider wheels/tires.

_Jeff
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Old 01-03-2006, 01:40 PM   #19
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Quote:
Originally Posted by Siper2
That may also be an issue of cost. The wheels were already in circulation overseas, so why produce something new?

But when they wanted to release the new-age car in the US, I'm sure that a 16" version of the wheel they decided to use in Europe (remember it was the same wheel, just 17" instead) was the economical choice. And it likely just happened to translate to a 6.5" width.

One of those unfortunate coincidences, I think. I don't personally believe Subaru "removed" 0.5" to spite anyone.

=S2=
Those two wheels are pretty different. They just look similar because they're both split 5 spoke. There were a lot of wheels available to use on the WRX at the time if cost was the issue. At anyrate, it's all speculation.
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Old 01-03-2006, 01:52 PM   #20
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Quote:
Originally Posted by THAWA
Which explains the release of the WRX how?
Our watered-down pathetic excuse of a WRX, you mean?
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Old 01-03-2006, 01:58 PM   #21
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The short answer is MONEY.
Cheaper to make the wheel 16X6.5 than 16X7.0

The good news is that they finally got wise and we get 17X7.0 on the 06+ WRX
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Old 01-03-2006, 02:18 PM   #22
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Quote:
Originally Posted by dbrier
The short answer is MONEY.
As a previous poster mentioned, it might also have to do with the fact that a 6.5" wide wheel is the ideal width for the 205/55r16 tire that Subaru spec'd.

Of course, I think most of us would agree that the RE-92 HAD to be a Money-based decision, so perhaps it was the Money decision on the tires that resulted in the narrower wheel size.

As to why they didn't do this on the GC-era cars, well, it was a relatively limited run, and they already had the 7" wide wheel, which was a better match for the 205/50r16 tire they were putting on the cars for the rest of the world. Ironic as it may seem, they probably didn't want to spend the money to create a narrower wheel for the old RS, so they slapped the cheapo tires on 16x7 wheels. In a weird way, the reason the RS got 7" width was probably to SAVE money, while the newer WRX got a narrow wheel to better-match the stock tire.

_Jeff
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Old 01-03-2006, 03:35 PM   #23
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Quote:
Originally Posted by Portly
As a previous poster mentioned, it might also have to do with the fact that a 6.5" wide wheel is the ideal width for the 205/55r16 tire that Subaru spec'd.

Of course, I think most of us would agree that the RE-92 HAD to be a Money-based decision, so perhaps it was the Money decision on the tires that resulted in the narrower wheel size.

As to why they didn't do this on the GC-era cars, well, it was a relatively limited run, and they already had the 7" wide wheel, which was a better match for the 205/50r16 tire they were putting on the cars for the rest of the world. Ironic as it may seem, they probably didn't want to spend the money to create a narrower wheel for the old RS, so they slapped the cheapo tires on 16x7 wheels. In a weird way, the reason the RS got 7" width was probably to SAVE money, while the newer WRX got a narrow wheel to better-match the stock tire.

_Jeff
...no....I think THAT one was due to needing an AS tire with a 'V' speed rating so they could sell the car as a 4 season vehicle
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Old 01-03-2006, 03:46 PM   #24
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Quote:
Originally Posted by Uncle Scotty
...no....I think THAT one was due to needing an AS tire with a 'V' speed rating so they could sell the car as a 4 season vehicle
Of course, then we could get into the debate of why Subaru didn't pick something better, like, oh, say, the SP5000s.

But, yes, I see your point.

_Jeff
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Old 01-03-2006, 04:15 PM   #25
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Quote:
Originally Posted by Portly
Of course, then we could get into the debate of why Subaru didn't pick something better, like, oh, say, the SP5000s.

But, yes, I see your point.

_Jeff


...because the re92's are quiet and smooth and squishie and very OEM and don't make granny think that her car is harsh or loud or high performance or

the sp5000 isn't 'oem enough'
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