# For 225/40R18 - what wheel size? 18x7.5 or 18x8.5



## wolf1point8 (Jan 11, 2002)

New to the tire stuff, and this may be a bassackwards way of fitting tires to wheels, but I have searched around and haven't found my answer. I'm looking to find what the difference is between these two rim widths (besides the obvious inch), and what effect they have on overall wheel height, etc.? The 8.5 width has a 35mm offset and the 7.5 width has a 33mm offset. thanks for any help you can offer.


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## Sheep (Dec 21, 2000)

*Re: For 225/40R18 - what wheel size? 18x7.5 or 18x8.5 (wolf1point8)*

Std OEM overall diameter on VAG cars is 25", give or take a 1/10" depending upon brand installed....not matter what size or style wheel. You can install a 225/40x18 easily and safely on either one of those rim widths. I have 18x8.5" wheels with that size tire on my TT....it will also work on a Mk4. You will not get a stretched look (which I can't stand) with 8.5's but "bulge" in sidewall is very modest as opposed to narrower rim widths so you need to be especially careful you do not touch a curb...rim protectors will probably not even save the wheel in light touch on 8.5's. The only problem is with an 8.5" width wheel in ET35, you may need spacers (front is problem area). I had 18x8" ET35 with 225/40x18's on my Jetta with H&R/Bilstein spt with enough clearance, but 8.5's are going to be very close on backside to suspension/brake lines. And if you install coilovers, you will definitely need spacers.
My Jetta had 8mm H&R spacers on rear only to line up wheels with front and get them closer to fender lip.
With an ET33 on 7.5" rim, they will sit considerably inside fenderwell, so you'll need spacers front/back to get them lined up better....but plenty of clearance on backside. Remember that the rear wheel track on Mk4's is .8"/20mm less than front track, so if you use spacer up front, you should spacers on rear that are 10mm thicker than fronts. EX: 5mm up fronts, 15mm on rears. Jettas have very larger fender flare compared to other Mk4's. If you don't use spacers up front (which I prefer), then use 10mm each side in rear. My 8mm's were close enough.
If you need pics, I can email you couple of both cars for comparisons of tire/rim.


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## wolf1point8 (Jan 11, 2002)

*Re: For 225/40R18 - what wheel size? 18x7.5 or 18x8.5 (Sheep)*

Thanks for the info. I was basically wondering how the width would affect overall height and "bulge" around the rim. seems the 7.5 would have more bulge and be slightly taller and the 8.5 would have less bulge and be slightly shorter.
Found a great thread http://forums.vwvortex.com/zerothread?id=1197287 with lots of pics of basically the same setup that i'm looking for. Looks great.


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