I was looking at the BBS SR wheels that are 17x7.5 but they have the 45 mm offset instead of the 38 mm offset. Does anyone know if these will fit without damaging my car or negatively effect performance?
Thanks!

 

Don't know straight up since there are sometimes variances between cars, you may have adjusted camber, and it'll depend to an extent on your tire size, etc... but here's how you can find out:

1) Easy way: Go to the TireRack.com website, choose Volvo 850R and see if any of the wheels there have this width and offset. I just did, and it turns out one does have a 45mm offset. Looks really good so far... BUT Tire Rack kinda counts on you going with the stock tire size (205/45/17), and if you're wider than that you'll want to make sure...

So...

2) Measure your current wheel and tire setup (offset and tire size), and check the minimum clearance between the INSIDE of the tire and any "hard points" in your suspension at the rear, and in the front also measure clearance with the underbody/chassis when steering is at full lock left and right. If your current wheel is 38mm and you're at 45mm, that alone moves the inside of the rim and tire 7mm (just over 1/4") closer to the hard points. (However, the Volvo Volans rim is already a 42mm, so the movement is only 3mm, about 1/8")

+ ADD TO THAT that each 1/2" of RIM WIDTH moves that inner edge ANOTHER 1/4" closer to the hard points.

+ Increasing TIRE WIDTH (say, going to a 215 instead of a 205) brings the inside edge of the tire ANOTHER 50% of that increase closer to the hard points... from 205 to 215 means 5mm, about 1/4".

So... If you go from a Volvo Volans 7" wide rim 42mm offset to a 7.5" BBS 45mm offset, you're bringing the inside edge of the tire just a tad over 3/8" closer to the hard points. Going to a 215 tire can mean another 1/4" or so.

Note that tire widths vary between brands, so leave some "wiggle room"...

My guess would be going with the stock tire size at 205/45/17 and the wider rim would be just fine, but your mileage may vary...

Hope this helps!

 

the extra offset of 7mm moves the inside edge of the rim about 1/4 inch towards the strut. The extra 1/2 inch of rim width adds another 1/2 inch vs stock 6.5 inch rims. So if you have more than 3/4 inch of clearance on the inside of your stock rims to the strut, you should be good. As noted by Dixon, this assumes you go with a stock tire size of 205/45/17