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Re: 18x7.5 w/ 45 offset?? (zact5)

My wheels are 17x7.5 with 45 mm offset. Tires are 225/45/17. It fits just fine. The wheelbase is a bit wider, and the tires are wider. The tires are very close to the edge of the car, but not past it. There is no problem with rubbing the outside. There is no problem with rubbing inside on maximum turning.<p>Most likely 18x7.5 with 225/45/18 or 215/45/18 will work. Note 215/45/18 is a bit larger in overall diameter, but the fitment should otherwise probably be fine. Note that the tire bulge on 18 inch tires is LESS than 17. So if 225/45/17, then 225/40/18 will definitely fit (and has for many people). I think some have used 235/40/18 (which is larger than stock diameter).<p>As far as acceptable offets: that's a complicated subject, but I made my own opinion after reading a lot of stuff and talking to Tirerack. I tried to keep the offset close to 52.5 mm stock offset, but it's really hard to find wheels for our cars. I decided 45 mm minimum offset was okay. There are excellent wheels at 42 mm (Evolve R5 17x7.5 and Ronal R41 17x8). There are also 40 mm offset wheels on Tirerack that come up in the search. All of these will probably fit just fine.<p>I didn't want to go lower than 45 mm due to scrub radius. I and others might have posted more about this in other postings. 45 mm is a 7.5 mm change in scrub radius. So what? It affects steering feel, wear and tear on wheel bearings, who knows what else. Too big a change means too much wear and tear, and screwing up the carefully designed suspension geometries. With the 45 mm offset wheels I have, I can feel two interesting things:<p>- steering at low speeds is a bit more difficult (which I was hoping for!!!). But I don't know if the sticker tires are the reason.<br>- When I turn the car, I can actually feel a VERY SMALL amount of car lifting, where the inner side of the car lifts up a very small amount. This is arguably GOOD because it means the car is lifting in response to the inner side of the car pushing down MORE on the road. That means better front weight distribution in turns. <p>All in all, I really like my new wheel / tire setup.<p>Unfortunately, I don't really know anything about cars. Only what I glean from reading this or that. Lots of folks say 42 mm is no big deal. Then other folks say that officially you're not supposed to change by more than + / - 5 mm. So it's anybody's guess!!!<p>In the future, I might try to get 17x8 wheels with 48 mm or more offset custom made at teamdynamicsracing.com.<p>I will try to post pictures, but I haven't gotten around to it. Still, mine are 17 inch. Maybe not interest most wheel aftermarket folks!!!<p>
 

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Re: 18x7.5 w/ 45 offset?? (bassman)

Hey, that is good info. I'm also shopping for new wheels as I have decided to ditch the AS tires and go with separate summer / winter sets.<p>I already got new wheels for my wife's Taurus and that was a struggle. The Taurus has factory offset of 42mm (6x16 wheels with 215/60/16 rubber) and the first wheels I got had 38mm. They were listed as fitting with the 225/50/17 tires I wanted but they rubbed regardless. So they ordered another brand wheels with 40mm offset and they seem to fit now. I'm going to test that very carefully to be sure there are no rubbing issues any more. BTW, that is one of the few cars that have the same bolt pattern as our Volvos. <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/wink.gif" BORDER="0"> <p>I have tried to research which wheels really fit to my Volvo but that has proven difficult as well. I searched this forum too and got some numbers but too many different answers (ranging from 43mm to 52.5mm) as well. So, if someone has the official numbers, I'd like to know:<br>- factory offset of 6.5x16 wheels<br>- factory offset of 7x17 wheels<br>- factory offset of 7.5x18 wheels<p>I'm still trying to decide between 16 and 17 wheels but because Volvo has 18 wheels as well, I'm curious about the offset. Besides, there seems to be some 7.5x17 wheels available as well.
 

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Re: 18x7.5 w/ 45 offset?? (FinnSpeed)

I'm also looking at 19x7.5. But I don't want the car to be lifted. Anyone no how much of a drop to get rid of the fender gap on 18's and 19's?<p>Thanks for the info.
 

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Re: 18x7.5 w/ 45 offset?? (FinnSpeed)

S40/V50 factor wheels have 52.5 mm offset. That will be true for the 16x6.5, 17x7, and 18x7.5 wheels. The offset will locate the turning center of the tire. It *should* be the same for all wheel sizes. Offset compares the middle of the tire to the wheel mounting hub. It is therefore not related to the width of the wheel. How well the wheel fits in the car relates the width of the wheel, where it is mounted, and how far the center of the wheel is from the mounting (offset). There are good internet calculators for this stuff.<p>I believe S60/V70 is 49 mm offset, as therefore are all the 17x7.5 wheels for that car. I believe the Pegasus 17x8 and 18x8 wheels are 46 mm offset.<p>I thought about a 17x7.5 S60 wheel for my V50, but the bore size is not the same. Search for other postings on this issue, probably searching for "hubcentric ring." Getting a ring is problematic.<p><A HREF="http://forums.swedespeed.com/zerothread?id=61607" TARGET="_blank">http://forums.swedespeed.com/zerothread?id=61607</A><p><br>Bassman<p>
 

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Re: 18x7.5 w/ 45 offset?? (bassman)

Thanks!<p>I was just thinking that maybe Volvo had to decrease the offset a bit for 7.5 inch wide wheels because the best fitting tires are wider than 205, just to avoid rubbing the struts. So that was not the case. There was discussion if limiters are needed with 7.5 x 18 wheels and it might just be that 52.5mm offset results in the tire rubbing when turning tightly without them. Then, 45mm offset might fix that problem.<p>I know that regardless of the wheel width, you should keep the original offset unless you want changes in the steering and road feel. I noticed the 4mm per side difference in my wife's car and now that it is only 2mm, it feels better.<p>Now it seems that most of the wheels that Tire Rack is offering for our cars are useless unless you want to make a huge compromise with the offset. Majority of them has +40mm offset and I would not even consider those. They do have some with +48mm offset and a couple with +46mm and +47mm that might be OK but absolutely none with the factory offset. <IMG NAME="icon" SRC="http://www.vwvortex.com/zeroforum_graphics/screwy.gif" BORDER="0">
 

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i have evolve 19x8.5 at 35et and they rub at the rear when i hit a bump. <p>i can tolerate it. we should stick to no further than 40et<br>
 
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