I am helping out a mate who has been stickered for 17" rims on his 1200 ute.
he is going to borrow a set of stock standard 165/75/13 s
to get over the pits.

What are the rules? Is it no more than +- 5% in circumference?

thanks MIKE.
Interesting reading--assuming the original size for a 1985 1200 ute is 155/80/12, it looks like the overall diameter of the stock Sunny 165/75/13 is more than the permitted 15mm increase. Bugger!

Can someone confirm orig sizes for an 85 ute?

155SR-12. All 1200 utes, even the 1994 japan ones used 12" wheels

You're mixing up tyres and wheels.
The overall diameter of any tyre fitted to a passenger car....must not be more than 15 mm larger.....than any tyre designated by the vehicle manufacturer for that model

Confused? He's exactly correct.

165/75R13 is 22.7" diameter
155/80R12 is 21.7" diameter

Difference is 1" or 25mm

The 'standard' original tyre size on the 1971 to 1973 Datsun 1200 was 600x12. This is the original cross ply tyre & it was the 'default' [read 'STANDARD'] size from new, in Australia.

This measures out at 574mm diameter for highway traction tyres according to my 1988 Tyre & Rim Association Australia. Standards Manual.
Deep traction tyres measured 589mm & I have presumed that this means winter tread types.

The 155SR12 tyre was not 'standard' equipment, but was an OPTION at extra cost & these measured 554mm in diameter for highway traction tyres or 560mm for deep traction types.

So, .... as I see it, you can most certainly use 574mm as a base reference & one can even try the 589mm size plus the percentage & see how it goes.

In the end, it's not the wheel size, it's the tyre diameter that counts.

In my case I run 185x60x13 on the front & at 552mm it's well within the minimum limit. I also use 205x60x13's on the rear & at 576mm this too is well within limits.

Thanks DD
definitely against the rule book BUT the car passed through the pits easily and the overall diameter was not questioned

Interestingly the WIDTH rules say the max allowable width is 130% of original equipment
1.3 * 155mm = 201.5mm
so apparently everyone using 205 /60/ 13 in West Australia is illegal. I suspect the examiners turn a blind eye to this.

haha you could use 185 tyres on an 8 inch rim

streched hehe

oh but there not legal either :(