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I have a question regarding wheel offsets....is there much difference between a +40 & +42 offset?

I looking at upgrading my standard 16" wheels of my NB8B into a set of 17x7s. The only thing is the offset of the 17" wheels are +42 (as opposed to the +40 of the standard wheels)?

Is there going to be much difference? I would have prefered to keep the standard offset of +40, then most of the width gained would have been pushed out. But I'm afraid the wheel I like doesn't come in that offset.

PS. My car hasn't been lowered.

Try this http://www.1010tires.com/WheelOffsetCalculator.asp

please oh please don't get 17's, its not an upgrade, its a downgrade, an upgrade would be 15's

But if you must, the difference between those offsets is 2mm, is that much?? You tell us. You need to give a context, eg, how does it affect handling or looks or fitment.
So the wheel will be moved toward the centre of the car by 2mm. You must also check the wheel width, so if its wider, its wider on both sides by half the amount.

Usually you'd go for a wider track for better performance, more -ve offset, somewhere in the 20's. But seing as you're getting 17's i take it you're not that into performance so you probably wouldn't notice the difference in 2mm of offset, you will notice the weight difference though, unless you are super rich and getting big, light forged wheels, if you were you would have done more research and be getting a lower offset.

So, it should theoretically be not much different taking weight out of the eqn.

Ozchris

Thanks for the tool. This visualised the difference for me. I was more worried by the width it will take up inwards. Gaining 8mm width inward shouldn't be too much of a problem.

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Sasso

These are going to be for my road wheels, hence I called them an upgrade. Purpose of these new wheels are both to personalise my ride and hopefully do some tasteful updates. I've had my NB8B since new (2002) and have not done any changes to it - apart from a RB2 bar and leather. So this is the next step to put some individuality into it.

Wheels are light considering they are 17x7s. They only weight 7.9kgs each (about a kilo more per corner from std). Weight was a considering factor of my choice.

I'm keeping my original 16s for the track, and this time since I don't have to compromise for road use, I can put semi-slicks onto them now.

mate for the track I would get some 15x7's and an offset of mid 20's. You could probably do a straight swap for your 16's that way track tyres will be much cheaper and you will have even less unsprung weight. I am kind of with you on the visual front for the street. If you can tell the 2kgs per corner difference on the road you are probably driving illegally. good luck with it mate and remember to post pics!

holy crap for 7.9kg what are they diamond studded. I wouldn't recommend going over 6kg unless they were damn good wheels with dish, eg equip 03's.
Then again I haven't seen the wheels you want so they might be worth it.

I agree with 16bit 15's for track is more sensible.

You'll feel the extra weight in the wheels every single time you take off from the lights, reverse into a carpark, inch the car forward in traffic...

Got the wheels today, weighed them and they're only 7.2kgs. I thought they were more 8kgs. So they're less than a kilo more than the stock 16s. Not bad considering they're 17s.

First choice was the Rays Wheels' VOLK Racing CE28N. But considering they were over $400 each. I've settled for the Motegi Racing SP10s

Will post some pix after they've fitted.

Nice rims. Still not sure about the weight though, you should run spaces to bring the offset a bit lower so it looks better, its got a FWD offset. Ahh shoulda got the Volks, yum yum yum yum.