18'' rims on a MX5

bruce · Postby **bruce** » Fri Oct 19, 2007 4:42 pm

Caedrus wrote:
From inside the car, they suck ass like a nuclear powered ass sucking machine.
.

Boags · Postby **Boags** » Fri Oct 19, 2007 6:35 pm

bruce wrote:
Caedrus wrote:
From inside the car, they suck ass like a nuclear powered ass sucking machine.
.

irwin83r · Postby **irwin83r** » Fri Oct 19, 2007 9:34 pm

legality wise im not so sure they are a problem...

correct me if im wrong but isnt the rolling dia the only thing they are concerned with not the rim dia..

meaning if you up size the rim you will have to lower the profile of the tyre to retain.../stay in the maximum change of rolling dia of 3%...

as far as width and track go they can only increase by 1\" or 25mm.

so... going by that (if im right) you can go as big as you like providing you can find rubber with a lower enough profile to keep it down in rolling dia.,

bruce · Postby **bruce** » Mon Oct 22, 2007 12:11 pm

No, I'm pretty sure it's rim size. I don't think they are concerned with diameter as it would be too hard to check (plus all the different profiles available would cause too much confusion).

16bit · Postby **16bit** » Mon Oct 22, 2007 12:42 pm

in qld i am pretty sure its up 2 inches only going down 5 series each inch.

JBT · Postby **JBT** » Mon Oct 22, 2007 12:54 pm

Qld rules are here.

meanmx · Postby **meanmx** » Mon Oct 22, 2007 7:07 pm

Do what you want wheel wise. There are a lot of people on here that are fanatical about not going any larger than 16 although 15 would be better. I personally have 17's on my NA and I wouldn't swap them. As long as the wheels are light the impact will be minimal although there will be some issues with going heavier rim. Up to you to decide whether you want that or not. 18's will definately fit your car though and will look awesome in my opinion.

Ben

irwin83r · Postby **irwin83r** » Mon Oct 22, 2007 8:06 pm

bruce wrote:No, I'm pretty sure it's rim size. I don't think they are concerned with diameter as it would be too hard to check (plus all the different profiles available would cause too much confusion).

theres a simple equation to work it out (though it escapes me) but more so i thought the reasoning behind this was to do with sending your speedo out..

if the rolling dia stays the same so dose the speedo reading... any link to NSW rules??

Charlie Brown · Postby **Charlie Brown** » Tue Oct 23, 2007 9:21 am

irwin83r wrote:
bruce wrote:No, I'm pretty sure it's rim size. I don't think they are concerned with diameter as it would be too hard to check (plus all the different profiles available would cause too much confusion).

theres a simple equation to work it out (though it escapes me) but more so i thought the reasoning behind this was to do with sending your speedo out..

if the rolling dia stays the same so dose the speedo reading... any link to NSW rules??

http://www.rta.nsw.gov.au/registration/ ... 9_rev4.pdf

StanTheMan · Postby **StanTheMan** » Tue Oct 23, 2007 9:27 am

NSW

http://www.rta.nsw.gov.au/registration/ ... 9_rev4.pdf

every state is a little different. I stumbled across SA one last night.....very detailed with cars before a certain manufacture date are not affected by offset. provided the tyre doesn't foul against anything & so on.

but personally it annoys the hell out of me when peeps start stating misinformation when its obvious they have never looked at this information.
This subject comes up every 6 mths everytime some clown thinks 1 inch up & 1 inch wider is all you are allowed or something similar.

OK if you know you are breaking the rules ....its your call. you are the one who may get defected. but most of us who have modded will most likely get defected in one way or another. I think we should ad these docs in a sticky for all the states to compliment the info we have now on suspension modifications thanks to MX5 racing

/off box
/rant
:mrgreen:

Ajay · Postby **Ajay** » Tue Oct 23, 2007 11:55 am

without looking at my tyre plaque cause im at work.. what size are the standard rims.. i know they are 14\" but what is the tyre size

Cheers
Ajay

Charlie Brown · Postby **Charlie Brown** » Tue Oct 23, 2007 12:19 pm

mx5_boy wrote:without looking at my tyre plaque cause im at work.. what size are the standard rims.. i know they are 14" but what is the tyre size

Cheers
Ajay

185x60x14 on 5.5" rims to '93