Guys i'm sick of seeing people say, "It's illegal to go more than 2 rim sizes up, eg from 15" to 18". IT'S NOT! At least not in QLD, NSW and VIC.
The main ones you have to look out for are:

Width, cannot be wider than 1 inch of the maximum available for that model or series, eg TJ and TJII had the option of 16x7 or 17x7 rims, so you can go ??x8 at most.

The overall diameter cannot change by more than 15mm, this is from one edge of the outside tyre to the other (so it spans accross the tyre, rim then other side of tyre). So you can go as big as you want, you just have to accomodate with lower profile rubber. Obviously you're going to hit a size where it's not logical, maybe getting into the 20's/21's etc.

Track size cannot increase by more than an inch/2 inches depending if you have FWD or AWD.
These are for QLD/NSW/VIC. If you disagree, post where it states i'm wrong!
If you want proof, i'll get up off my **** and find it, Vicroads VSI 8 has it, cant remember the nsw and qld ones, but they're in a fairly recent thread.

I'm just sick of hearing people give advice saying, you cannot go more than 2 inches bigger, this may be a policy enforced by your insurance company, but it definetly IS NOT a legal requirement.

Discuss :).
Thank-you.

Nope not in SA. You can only increase the diameter of the wheel by 50mm on top of the largest wheel on the tyre placard. But it doesn't specify a maximum diameter. Says so in the attatchments which are copies from the SA moding legal book thingo from Transport SA. The full book is in this post here (http://www.aussiemagna.com/forums/showthread.php?t=38466)

well done leigh!

thanks!:D

Yeah in SA the rules are:

2" increase in diameter of rim. Rolling diameter must stay the same though.
No limit on rim width as long as its inside the guards and does not touch anything at full lock either direction.

Guys i'm sick of seeing people say, "It's illegal to go more than 2 rim sizes up, eg from 15" to 18". IT'S NOT! At least not in QLD, NSW and VIC.
The main ones you have to look out for are:

Width, cannot be wider than 1 inch of the maximum available for that model or series, eg TJ and TJII had the option of 16x7 or 17x7 rims, so you can go ??x8 at most.

The overall diameter cannot change by more than 15mm, this is from one edge of the outside tyre to the other (so it spans accross the tyre, rim then other side of tyre). So you can go as big as you want, you just have to accomodate with lower profile rubber. Obviously you're going to hit a size where it's not logical, maybe getting into the 20's/21's etc.

Track size cannot increase by more than an inch/2 inches depending if you have FWD or AWD.
These are for QLD/NSW/VIC. If you disagree, post where it states i'm wrong!
If you want proof, i'll get up off my **** and find it, Vicroads VSI 8 has it, cant remember the nsw and qld ones, but they're in a fairly recent thread.

I'm just sick of hearing people give advice saying, you cannot go more than 2 inches bigger, this may be a policy enforced by your insurance company, but it definetly IS NOT a legal requirement.

Discuss :).
Thank-you.

It used to be the case Leigh, but the ADR compliance was changed in 2004..

yeah i was also under the impression that the 2 up 1 across was still the go. you know you can also go 2" smaller and 1 inch narrower? Dunno why you'd wanna, unless you have a drag car.

I've added the SA legislation to the FAQ (http://www.wermspowke.net/wiki/index.php/Wheels#State_Laws_on_Wheel_Modifications). If you have evidence of your state legislation then it would be a good idea to add that as well. Only add it though if you have evidence of the current law from the relevent transport assosiation though. We don't want bull**** being added there.

i reckon this 1" wider is silly

The cops will never know how wide the original rim is to an aftermarket one as the only thing that specifies on the placard is the width of tyre (not rim) and the diameter size. ie (R16 215)

So in other words if your stock rim is like mine (16x6) and I get a 17x7 rim, you can fit a 225 legally with no issues because its only 1" wider.
But if I get a 17x8 (2" wider!!) and put the same 225 tyre on there and they dont stick out past the gaurds the boys in blue wont be able to tell the difference.

Please correct me if I'm wrong.

Just go to your state's motor authority and ASK. Or go to their site. There are documents available to download.