tyres

[WaveCult]

damn

so how much does an engineer cost? like how much to get wheels engineered? how much to get raised suspension or lifted body?

have all the sierras i see out there been engineered or are there just heaps of dodgy ones?

thanks
mike

I vote on "heaps of dodgy ones"... anyone-else?

[Beastmavster]

damn

so how much does an engineer cost? like how much to get wheels engineered? how much to get raised suspension or lifted body?

have all the sierras i see out there been engineered or are there just heaps of dodgy ones?

thanks
mike

I vote on "heaps of dodgy ones"... anyone-else?

Mines dodgy until I can find a dodgy engineer

Or at least a reasonable one here in QLD

[WaveCult]

Did I mention uninsured?

Anyway, regarding rims I'm not sure about the width but in terms of size (15 vs 16) it is legal to go up one from the highest sized manufacturer optioned rim for your vehicle. So if Suzuki provided 17" rims as an option on your car (hypothetically speaking) you could go up to 18's... on the other hand if they optionned 14" rims you could go to 13" (this is all diameter, not width!).

In terms of tyres, my reading up on Victorian laws suggest the main concern is tyre diameter. You can only increase it by 10mm

(you can check tyre sizes on http://www.miata.net/garage/tirecalc.html)

Reason behind this, I suspect, is that bigger tyres throw your speedo out. Like mine for instance... I've got standard size 205/75R15 which were fine on the original tyres, but with a set of new Cooper Discoverer ATs, the speedo is actually 3kms slow at 60kms/h (showing 60, I'll be doing 63) and 4 at 80kms/h... luckily I didn't find this out the hard way!!

[greg]

Reason behind this, I suspect, is that bigger tyres throw your speedo out. Like mine for instance... I've got standard size 205/75R15 which were fine on the original tyres, but with a set of new Cooper Discoverer ATs, the speedo is actually 3kms slow at 60kms/h (showing 60, I'll be doing 63) and 4 at 80kms/h... luckily I didn't find this out the hard way!!

I agree - i asked a person at vic roads about this and that's what they said - speedo problem... i asked if i could get it "re-calibrated" - he said "no"...

anyways, i think you get used to having the speedo incorrect - mine was up around the 33% out - i.e. road speed = speedo speed x 1.333 so when i was doing 100 on the road - the speedo was ready 75...

chances are though - if you are changing your tyre size by this much, you will probably change your diff ratios too - and that gives you an opportunity to get your speedo back to at least close to be correct again.
Note: changing x-fer gears will not do this because the speedo reading is taken from the output of the x-fer case - therefore, even though your engine vs tyre speed will change, your speedo vs tyre speed will not.

Oh, unless you have another x-fer case behind the one that has the speedo coming off it - but that's another story.

Cheers.

[murcod]

There's a similar conversation about tyre sizes and legal issues in the Daihatsu forum here:

http://www.outerlimits4x4.com/PHP_Modul ... php?t=6615

From what I've found every state seems to only allow a 15mm overall increase in diameter.

That means I can't even go from a 225/70 to a 235/75 on my Feroza (37.5mm increase).

[Beastmavster]

Reason behind this, I suspect, is that bigger tyres throw your speedo out. Like mine for instance... I've got standard size 205/75R15 which were fine on the original tyres, but with a set of new Cooper Discoverer ATs, the speedo is actually 3kms slow at 60kms/h (showing 60, I'll be doing 63) and 4 at 80kms/h... luckily I didn't find this out the hard way!!

I agree - i asked a person at vic roads about this and that's what they said - speedo problem... i asked if i could get it "re-calibrated" - he said "no"...

Cheers.

AS far as I knew there's only one place in Melbourne whore are approved to do speedo recalibration - I can't remember the name of it but it's on Whitehorse Road Just before the Hungry Jacks at Ringwood (Heather Dale Road Intersection?).

Speedo accuracy requirement for ADR is only within 10% so a tyre variation of 205/75 to 235/75 should still technically be legal......

[Beastmavster]

There's a similar conversation about tyre sizes and legal issues in the Daihatsu forum here:

http://www.outerlimits4x4.com/PHP_Modul ... php?t=6615

From what I've found every state seems to only allow a 15mm overall increase in diameter.

That means I can't even go from a 225/70 to a 235/75 on my Feroza (37.5mm increase).

Solution to this is to find a "BIG" 225 and use that for your base measurements, or just use a big 225.

I've seen variations of 31" tyres from about 29" to 33" in real diameter. The cops arent gonna have exact manufacturer tyre measurements.....

[becky]

I run 235/75/15 on Becky & have never had problems with the constabulary. I live in qld so we are fairly restricted by our transport dept.

[MKPatrolGuy]

Reason behind this, I suspect, is that bigger tyres throw your speedo out. Like mine for instance... I've got standard size 205/75R15 which were fine on the original tyres, but with a set of new Cooper Discoverer ATs, the speedo is actually 3kms slow at 60kms/h (showing 60, I'll be doing 63) and 4 at 80kms/h... luckily I didn't find this out the hard way!!

I agree - i asked a person at vic roads about this and that's what they said - speedo problem... i asked if i could get it "re-calibrated" - he said "no"...

Cheers.

AS far as I knew there's only one place in Melbourne whore are approved to do speedo recalibration - I can't remember the name of it but it's on Whitehorse Road Just before the Hungry Jacks at Ringwood (Heather Dale Road Intersection?).

Speedo accuracy requirement for ADR is only within 10% so a tyre variation of 205/75 to 235/75 should still technically be legal......

That place would be Ringwood Speedometer Services, I had my speedo done there, cost me about $60 from memory.