Started a new thread as 2" lift and 31x10.5 is a popular combination and didn't want to hi-jack or get confused with all the other lift and tyre combinations.
And I made a couple of mistakes in my previous.
First the lift kit, then the tyre discussion.
I think Victoria is allowed 50mm lift + 25mm tyre lift without Engineering.
I looked up these TJ vehicle details at
http://myrta.com/rvd/searchRVD.do
Standard TJ 2003
P225/75R15 with +32mm Rim offset, Wheel track Front and Rear 1473mm
Unladen vertical measurement wheel centre to top of wheel arch.
Front 455mm, Rear 485mm
I bought my Jeep with a 2" lift detailed.
My Jeep measures 540mm wheel centre to arch.
If I focus on the front 540-455=85mm that was not a 2" lift kit, more like 3.5"
So at this point I blow the 50+25=75mm and already need Engineering.
Then I considered lowering to get back under 75mm.
As I read a bit it seems the max wheel center to arch increase is 2" 50mm.
And the max tyre increase is 25mm.
So I worked out the 31x10.5 increase for interest.
Stock rim = 15 inch = 381mm (rim only)
31x10.5 = 31 inch = 787.4mm (whole wheel and tyre diameter)
787.4-381= 406.4mm this is the two sidewalls of the 31x10.5 tyre
406.4/2 = 203.2 mm this is one sidewall of the 31x10.5
Stock tyre = 225x75 = 168.75 one sidewall
Stock tyre one sidewall - 31x10.5 tyre one sidewall = 203.2-168.75= 34.45mm
Did I do this wrong? Can't see how a 31x10.5 would ever be allowed in Vic??
It exceeds the 25mm allowable tyre lift.
And.. My Jeep would be a total increase of 85mm body + 34.45 tyre = approx 120mm total lift
So HELP... any informed answers would be appreciated.
Is the 50 lift +25 tyre lift without engineering correct?
Can I actually get 120mm Engineered?
What level of Engineering is this - a static inspection or the full swerve test?
Are 31x10.5 tyres ever actually legal on their own or even possible to engineer on a TJ?
All only in Victoria.