Thread: larger tyres

Originally Posted by lyonsy

lyhoon94 and steve_a
did you notice it drive any differently like tenancy to wonder over the road etc or pretty much the same?

as for braking distance becoming longer i am surprised i would of through the larger tyres would be better since there is more rubber on the ground and if i brake test my disco the abs goes nuts due to the wheels locking up

I had serious misgivings about the handling at first, I pretty much went to the Flinders the day after fitting and it felt skittish and a bit bum clenchy. However, after I deflated the tyres from 45psi all round (thanks for that tyre fitters!) it handles fine. A bit of vibration has gone (probably newly balanced) and nothing else noted.

Ahh, you know that the surface area has no effect on friction? It's counter intuitive but it's about the co-efficient and the vehicle weight. The longer braking is likely down to increased torque needed for the rotor to the wheel/tyre combo. It should naturally lessen as the loose nut behind the wheel tightens up I think the vehicle load has more effect on increased braking than tyre size changes IMHO.
Considering the various loaded weights we all run (and towed things like 1900KG campers) I reckon the tyre difference is the least of my worries.

bgkdavis

yep your correct they just worded it a bit screwy for one option with the lift they state 25mm radius
then with out a lift they state 50 diameter.

but ether way i am not worried cause i just get it engineered for them not hard or dear to do

btw link for 4wd modifications vic
http://www.victoriapolice4wdclub.org...20vehicles.pdf

I run 265 / 75 R16 with a 50mm suspension lift and adjustable panhard rod, I recommend doing this as it will put less stress on your front prop shaft double uni's which is a weak point.

The tyres do not scrub. The speedo reads 10% low, 100 is 110. You will notice it takes longer to get moving, it also increases your min speed when traveling down steep hills.

In the Vic High Country and Tassis I found this a bit of an issue, actually in Tas it was an issue driving up mount Wellington with the big tires too. In Big Desert it is ok, the only thing working against you is the lag time to get moving on the sand when trying some of those dunes and the sand bowl.

I've got mine about right now by using an Ashcroft V8 torque converter for the TD5, 1.4 ratio (Defender) transfer case, a TD5 remap and removing the CAT and EGR. At actual 100km/h the RPM is 2500 rpm at 110 its 2750 rpm.

That is my 2 bobs for what its worth. There is actually another thread similar to this at the moment, something i mentioned in that thread is the diff clearance on a Disco running 31in tires is about the same to a Patrol runing 33" tires. Interestingly enough they are both the legal max size for each car in VIC. So you will be able to take the same tracks as most other 4wds if you choose 31's. But 32" tyres will give you a little extra diff clearance with a compromise of power loss and crawling speed.