Jduke Posted August 30, 2005 Share Posted August 30, 2005 Finally found the right set of rims, superleggera's in anthr... Should have pics up tomorrow of them on the car... John D. Link to comment Share on other sites More sharing options...
PGT Posted August 30, 2005 Share Posted August 30, 2005 damn....where'd you find those? That's what I wanted when I first bought the car, but the anthracite was no longer made. Dibs when you decide you don't like these either Link to comment Share on other sites More sharing options...
Jduke Posted August 30, 2005 Author Share Posted August 30, 2005 Got lucky I think, found them on NASIOC in the new england forums. The kids has had them for a few years, had them on his WRX then bought a 05 sti. So he had to sell them. He is not giving them away paying $1000 even for the set. But local pick-up, so no shipping. These are def keepers... but I always say that. Link to comment Share on other sites More sharing options...
PGT Posted August 30, 2005 Share Posted August 30, 2005 are those Nokians on there?? Link to comment Share on other sites More sharing options...
Guest *Jedimaster* Posted August 30, 2005 Share Posted August 30, 2005 Nice wheels! Link to comment Share on other sites More sharing options...
Jduke Posted August 30, 2005 Author Share Posted August 30, 2005 yup nokian nry's. I have not heard much about these tires, but supposedly they are nice high performance summer tires, they have tread were indicators, that go from 1-8, and they are on 7 rear and 6 front now so allot of life left I think... Ill have to see how they ride tonight... Link to comment Share on other sites More sharing options...
HansGT Posted August 30, 2005 Share Posted August 30, 2005 Finally found the right set of rims, superleggera's in anthr... Should have pics up tomorrow of them on the car... John D. Shhhwing Link to comment Share on other sites More sharing options...
apexjapan2 Posted August 30, 2005 Share Posted August 30, 2005 Yummy - nice wheels and nice tyres. Link to comment Share on other sites More sharing options...
Nsaglibene Posted August 30, 2005 Share Posted August 30, 2005 Nice, those wheels really grew on me. Link to comment Share on other sites More sharing options...
SBT Posted August 31, 2005 Share Posted August 31, 2005 yup nokian nry's. I have not heard much about these tires, but supposedly they are nice high performance summer tires, they have tread were indicators, that go from 1-8, and they are on 7 rear and 6 front now so allot of life left I think... Ill have to see how they ride tonight... Very nice wheel/tire combination, I like it a lot. Just a note of caution though - Sounds like they are more worn on one end than the other and therefore you might want to think about not putting them on your car. If there's different wear between the fronts (WI @ 6) and rears (WI @ 7) then don't put them on as you'll risk damage to your drivetrain. Measure their outside circumference at the proper tire pressures before you put them on and if there's more than 1/4" difference front to rear then I'd not run them on the car. See Subaru's Website quoted here: "WARNING: All four tires must be the same in terms of manufacturer, brand (tread pattern), construction, degree of wear, speed symbol, load index and size. Mixing tires of different types, sizes or degrees of wear can result in damage to the vehicle's power train. (italics/bolding mine) The Subaru website, in another location, specifically mentions the > 1/4" rotational difference between tires but I'm not able to find it now. Will track it down though. SBT - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
tantal Posted August 31, 2005 Share Posted August 31, 2005 SBT, I don't think a diff of ~ 1/8 total wear is going to make a diff, although you may be right. Jduke, I'd recommend putting the more worn tires on the rear, and skip 1/2 to 1 rotation (i.e., if you normally rotate at 5k mi, wait until 7.5 or 10k before you rotate these) That ought to even out your wear. Again, while sbt may be right, I think that that difference is not significant. Worth checking I like those wheels too. Enjoy! Link to comment Share on other sites More sharing options...
SBT Posted August 31, 2005 Share Posted August 31, 2005 In my experience with Manual Tranny Subarus, 1/4" of rotational difference can make the car buck in stop and go traffic and during deceleration in lower gears, i.e., 1st and or 2nd gear slow down, jerk, jerk. The reason for this is that the speed difference between the front/rears is accumulating in the center differential and then re-releasing through the driveline causing the jerking. Would not have believed this unless the master tech had pointed it out to me and I had done the measurements front to rear. That's why I won't put a new tire on with three others that have mileage wear on them (usually > 2K miles) without measuring circumference. Sure it's time consuming but longevity and comfort-wise, it's worth it IME. SBT - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
forestir Posted August 31, 2005 Share Posted August 31, 2005 I'd read the 0.25" rule as well. Could have been on EndWrench or the owner's manual. Link to comment Share on other sites More sharing options...
tantal Posted August 31, 2005 Share Posted August 31, 2005 SBT, not disagreeing with you on that point at all - Its that I don't think there'll be 1/4" diff on those tires, that's all. 1/4" is a LOT considering the tread depth when new is probably no more than that - 10/32 is 1/4 plus 1/16, and some tires come with less tread. Link to comment Share on other sites More sharing options...
PhilT Posted August 31, 2005 Share Posted August 31, 2005 SBT, not disagreeing with you on that point at all - Its that I don't think there'll be 1/4" diff on those tires, that's all. 1/4" is a LOT considering the tread depth when new is probably no more than that - 10/32 is 1/4 plus 1/16, and some tires come with less tread. But didn't he say 1/4" of rotational difference ? Thats around the circumference of the wheel, so only 0.080" of wear on the diameter, and 0.040" on the tread. ?? That's not much at all. Double Award Winning Legacy GT Wagon Link to comment Share on other sites More sharing options...
tantal Posted August 31, 2005 Share Posted August 31, 2005 But didn't he say 1/4" of rotational difference ? Thats around the circumference of the wheel, so only 0.080" of wear on the diameter, and 0.040" on the tread. ?? That's not much at all. OOps, good point:redface: So that's tight. If 0.04" would be almost out of spec, then that's 1/25th of an inch, close to 1/32. Can't believe it's that tight, but there it is. Still if those wear bars are printed in increments of 1/32 of an inch (seems quite likely; from 9/32 down to 2/32, yes?), he should still be in good shape, since the spec says 1/25 (larger than 1/32)? Does that make sense or is it time for another martini? Good conversation. My brother keeps telling me not to rotate to keep down treadnoise Course, he has an M3 with staggered size & directional tires, so kinda hard to rotate. Link to comment Share on other sites More sharing options...
SBT Posted August 31, 2005 Share Posted August 31, 2005 I understand what you mean. What I was mentioning (not very clearly I might add) was that we're talking about 1/4" of rotational difference, not 1/4" in tread depth difference which would make a significant change in the circumferential difference. Let's look at a hypothetical example Take a stock new RE92. Stock diameter is 24.6 so that makes the outside circumference ~77.283". When you wear down 1/4" of circumference you don't wear down 1/4" of tread depth, you just decrease the rolling circumference by 1/4". Now put a new RE92 on one axle and keep the remaining worn tires in their current location. What do you have? You have at least 1/4" rotational difference between two tires on one axle (we'll assume the front "open diff" axle) and you have at least 1/4" rotational difference between the new front tire and the rears. This also assumes that the remaining tires were rotated normally and that tire pressures, tire balance and all other factors keep the outside circumference of the 3 remaining tires the same. In this example the older tires will turn faster than the newer tire given the newer tires greater outside circumference. This causes "bind" and premature wear on the drive line. If this is on the rear axle, the LSD will constantly try to correct and the car will pull as one side accelerates faster and slows down faster than the other. I have personally experienced this on my 98 LGT. Now for the math (please excuse the labor of love) The diameter on the new Nokian NRY 215/45x17 = 24.6 Two of Jduke's tires are at Wear Indicators (WI) 7 and two are at WI 6 respectively. There are 10.8 "32nds" of tread and 8 tread wear indicators so let's assume that: one (1) tread wear indicator is roughly .0422" of tire. (1/32 x (10.8/8)) or (1/32 x 1.35) = .03125 x 1.35 = .0421875 so, two (2) tread wear indicators would be roughly .0844" r = radius (d/2) d = diameter (r x 2) c = circumference (pi x d) pi = ~3.14159265358979323846... Nokian NRY new radius = 24.6 / 2 = 12.3" Nokian radius at WI 7 = 12.3 - .0422 = 12.2578" Nokian radius at WI 6 = 12.3 - .0844 = 12.2156" Nokian diameter at WI 7 = 12.2578 * 2 = 24.5156" Nokian diameter at WI 6 = 12.2156 * 2 = 24.4312" Nokian circumference at WI 7 = 24.5156 * pi = 77.018" Nokian circumference at WI 6 = 24.4312 * pi = 76.753" Given the tread WI on Jduke's tires, the circumference on the NRYs at the first wear indicator (-.0422") would equal roughly 77.018" and at the first wear indicator (-.0844") would equal 76.753". Circumference difference = 77.018 - 76.753 = .2675" or > 1/4" Now the question becomes, are any of the four tire's circumferences greater or less than the computed circumferences above. If they are then you potentially have even greater circumferential differences. As always, YMMV. SBT - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
tantal Posted August 31, 2005 Share Posted August 31, 2005 Dude, nice thesis I'm with you on all that - I get your point and I agree with you. I don't agree with your calculation regarding the treadwear indicators, though. A tire is legally considered worn out if it has 2/32 of tread or less. So, if there are 10.8/32 of tread, then the diff would be from 10.8 to 2, or to make it simple, one treadwear indicator is about 1/32 of an inch, and he's ok. I cant believe they'd use tread indicators below 2/32. Anyway, that would satisfy me. You're more knowledgeable than me, but I think I'm right LOL do you know where the last treadwear indicator is? i.e., at 2 or 0/32? Otherwise your math is inarguable. Good job I understand what you mean. What I was mentioning (not very clearly I might add) was that we're talking about 1/4" of rotational difference, not 1/4" in tread depth difference which would make a significant change in the circumferential difference. Let's look at a hypothetical example Take a stock new RE92. Stock diameter is 24.6 so that makes the outside circumference ~77.283". When you wear down 1/4" of circumference you don't wear down 1/4" of tread depth, you just decrease the rolling circumference by 1/4". Now put a new RE92 on one axle and keep the remaining worn tires in their current location. What do you have? You have at least 1/4" rotational difference between two tires on one axle (we'll assume the front "open diff" axle) and you have at least 1/4" rotational difference between the new front tire and the rears. This also assumes that the remaining tires were rotated normally and that tire pressures, tire balance and all other factors keep the outside circumference of the 3 remaining tires the same. In this example the older tires will turn faster than the newer tire given the newer tires greater outside circumference. This causes "bind" and premature wear on the drive line. If this is on the rear axle, the LSD will constantly try to correct and the car will pull as one side accelerates faster and slows down faster than the other. I have personally experienced this on my 98 LGT. Now for the math (please excuse the labor of love) The diameter on the new Nokian NRY 215/45x17 = 24.6 Two of Jduke's tires are at Wear Indicators (WI) 7 and two are at WI 6 respectively. There are 10.8 "32nds" of tread and 8 tread wear indicators so let's assume that: one (1) tread wear indicator is roughly .0422" of tire. (1/32 x (10.8/8)) or (1/32 x 1.35) = .03125 x 1.35 = .0421875 so, two (2) tread wear indicators would be roughly .0844" r = radius (d/2) d = diameter (r x 2) c = circumference (pi x d) pi = ~3.14159265358979323846... Nokian NRY new radius = 24.6 / 2 = 12.3" Nokian radius at WI 7 = 12.3 - .0422 = 12.2578" Nokian radius at WI 6 = 12.3 - .0844 = 12.2156" Nokian diameter at WI 7 = 12.2578 * 2 = 24.5156" Nokian diameter at WI 6 = 12.2156 * 2 = 24.4312" Nokian circumference at WI 7 = 24.5156 * pi = 77.018" Nokian circumference at WI 6 = 24.4312 * pi = 76.753" Given the tread WI on Jduke's tires, the circumference on the NRYs at the first wear indicator (-.0422") would equal roughly 77.018" and at the first wear indicator (-.0844") would equal 76.753". Circumference difference = 77.018 - 76.753 = .2675" or > 1/4" Now the question becomes, are any of the four tire's circumferences greater or less than the computed circumferences above. If they are then you potentially have even greater circumferential differences. As always, YMMV. SBT Link to comment Share on other sites More sharing options...
SBT Posted August 31, 2005 Share Posted August 31, 2005 Thanks for the "thesis" compliment lol. The website I checked for the NRY specs indicated that there was 10.8 "32nds" of tread but did not indicate whether the 10.8 32nds took you all the way to "0/32nds" or just to "2/32nds". I just interpreted that to mean that each of the eight tread WIs were evenly dispersed across the entire tread and therefore could not be 1/32" for each WI. If that's not the case, then the math is simpler: WI 7: 12.3 - .03125 = 12.26875 * 2 = 24.5375 * 3.14... = 77.087" WI 6: 12.3 - .06250 = 12.23750 * 2 = 24.4750 * 3.14... = 76.890" 77.087 - 76.890 = ~.20 or < 1/4" which should be okay initially. The only way to know for sure is to measure the outside diameters. I would worry about the WI 6 tires wearing down more quickly, especially if they are put on the front. It would not take long for that .20 to become > .25 in that situation. Really not trying to belabor the point, just wanted to offer a word of experience and a caution about using circumferentially different tires on our Subes. SBT - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
tantal Posted August 31, 2005 Share Posted August 31, 2005 SBT, we're good! Like to get to the bottom of things. That way when we forget about it, and we argue about it again, somebody can run a search and put in a link to this thread so we remember the answer. LOL I'm just glad I found out I can't tolerate more than 1/32" wear diff. between my tires on my awd cars. Sounds like it's a lot in the big scheme of things, but it isn't, is it? Link to comment Share on other sites More sharing options...
SBT Posted August 31, 2005 Share Posted August 31, 2005 Yeah, in the rounder scheme of things 1/32" is a big deal... Have a good one. Signing off for the night. Time to take the dog for his nightly constitutional and get my butt out of this chair. SBT - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
Jduke Posted August 31, 2005 Author Share Posted August 31, 2005 Wow you guys really worked this over... nice to see so much passion for tire wear... So, it seems the wear indicators were not that far off from all being 7, he had just rotated them before he took them off and the fronts were about 6.5-7, and the rears about 6.5. so pretty even in my mind. Although it seems there is more to it than that. Dont have pics yet, need battery for the camera, and its pouring up here in VT today. So we will see. They do really look good, much better than I had expected, this is my third set of aftermarket rims I have had on the LGT so far (just could not settle on the look I wanted) and the first glance in daylight this am I knew I had made a good decision. They go with the car very well. Link to comment Share on other sites More sharing options...
Gordon05GT Posted August 31, 2005 Share Posted August 31, 2005 BLah Blah Blah...............nice rims though! Link to comment Share on other sites More sharing options...
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