GQ RB30 manaul - 225/75 R14 tyres - healthiest diff ratio

[dom14]

Hi Guys,
I'm just wondering whether 4:3 diff or a different ratio(4:1, 3.9, etc) diff more suitable for the my RB30?!
The reason for the question is that because I'm running tyres smaller than the standard on road all the time(225/75 R16).
Currently, it has 4:3 ratio diff, which I'm not totally sure the right thing for the tiny tyres I have on it.
Thanks in advance for any help, suggestions.

[Bloodyaussie]

Why would you run such a small tyre.... that can have the opposite affect on economy as your car would be revving higher at certain speeds???

[dom14]

Why would you run such a small tyre.... that can have the opposite affect on economy as your car would be revving higher at certain speeds???

Sorry mate, I meant, R16.
Can one of the admins correct the heading, please? Its' 225/75 R16.
Thanks

[fourj]

Hey Dom 14
That's about a 29 inch tyre, by my reckoning 4.1 ratios would bring you back as close to standard as possible. However do you really want to go that way? If it's only a short term fix, I would just live with the 4.3 ratios.

[dom14]

Hey Dom 14
That's about a 29 inch tyre, by my reckoning 4.1 ratios would bring you back as close to standard as possible. However do you really want to go that way? If it's only a short term fix, I would just live with the 4.3 ratios.

Hi fourj,
I think, it would be a temporary fix mate. My idea is to chuck in a 4:1 ratio rear diff which apparently are easier to come by and cheaper, while I'm getting mine properly fixed.
That should be ok, as long as I stay away from engaging the 4WD, shouldn't it? I think RB30's meant to stay with 4:3 ratio for the sake of the smaller gearbox & the motor it comes with(correct me if I'm wrong though).

[fourj]

Yeah stay out of 4by should be ok. 4.3 ratios are right for RB30s.