New Zealand Datsun Club

85_Z31 wrote:Been out to do some measuring...

43m ( hub to pad carrier ) minus 12.1 leaves me 31mm from the face of the hub to the center line of where the rotor needs to be.

By looking at the Jag Drawing the inside of the rotor hat Minus half the thickness of the rotor leaves 15.5 ( face of hub to center line of rotor)

So by those measurements this should completely work providing I use a 14.5mm Spacer

If somebody cares to check my maths that would be appreciated.

Hi James,

I've only had a quick glance but I'd say from the inside of the rotor hat to the rear of the rotor minus half the thickness of the rotor would be between 14.7 mm and 14.3 mm due to the tolerances shown on the diagram.

Feel free to point out that I'm wrong, surely I've missed something here

Also, if the pad carrier is 24.24 mm jaw to jaw, and your new disk is approximately 20 mm thick, how will your brake pads fit in there?

Mikewazowski wrote:

85_Z31 wrote:Been out to do some measuring...

43m ( hub to pad carrier ) minus 12.1 leaves me 31mm from the face of the hub to the center line of where the rotor needs to be.

By looking at the Jag Drawing the inside of the rotor hat Minus half the thickness of the rotor leaves 15.5 ( face of hub to center line of rotor)

So by those measurements this should completely work providing I use a 14.5mm Spacer

If somebody cares to check my maths that would be appreciated.

Hi James,

I've only had a quick glance but I'd say from the inside of the rotor hat to the rear of the rotor minus half the thickness of the rotor would be between 14.7 mm and 14.3 mm due to the tolerances shown on the diagram.

Feel free to point out that I'm wrong, surely I've missed something here

Also, if the pad carrier is 24.24 mm jaw to jaw, and your new disk is approximately 20 mm thick, how will your brake pads fit in there?

oh the pads sit in there fine, the caliper i am using is designed for 20mm thick rotor the 24.4 measurement is the machined out groove where the rotor sits and the pads sit either side of that in some slots.

Also i think your right on the measurements, thanks for checking that out for me, the fact that your numbers are within 1mm of my numbers makes me happy

Also I have gone ahead and ordered the rotors for $86 each, I am confident this will work, but if it don't I won't be able to return the rotors due to having them re drilled. oh well - at least they were cheap.

85_Z31 wrote: oh the pads sit in there fine, the caliper i am using is designed for 20mm thick rotor the 24.4 measurement is the machined out groove where the rotor sits and the pads sit either side of that in some slots.

Also i think your right on the measurements, thanks for checking that out for me, the fact that your numbers are within 1mm of my numbers makes me happy

Also I have gone ahead and ordered the rotors for $86 each, I am confident this will work, but if it don't I won't be able to return the rotors due to having them re drilled. oh well - at least they were cheap.

Ah, I see what you mean about the pads fitting, I understand how it works now

Re the measurements, no problem at all. With the information that you have given I think it should work ok

P.S. I'm guessing the "spacer" you mentioned is to space the caliper/pad carrier out towards the front of the hub?

Mikewazowski wrote:P.S. I'm guessing the "spacer" you mentioned is to space the caliper/pad carrier out towards the front of the hub?

Yup that's exactly what i meant - you just explained it much better than me.

This is why i have gone for an unusually shallow rotor , you can always space the caliper out towards the hub but there is a whole bunch of reasons why you can't space it further back.

Sounds good. I'm keen to see how you get on with this.

Progress is Being made

Rotors are at the engineer being machined - told him I need them ASAP

Camber plates from like 10 pages ago have been stuck in limbo so i told the engineer i need them by the 20th.

Sent a list of things off to the Certifier to see if there is anything that needs changed before a full inspection

I guess if I want to make it to Akaroa I really need to ramp it up.

Looking good man, not sure if you saw my question from a couple of pages ago but just for my own interest how come you can't use the factory late Z31 rotors?

Who are you using to certify it? Wayne or Don?

I'm Using Wayne, mostly because Wayne knows that Justin Neil ( my useful engineer ) does things to a very high standard and when I spoke to Wayne today he quoted that "if it was done by Justin it will be all good"


And for your question about late Z31 rotors they are are simply to tall and hit the caliper mounting point

So the arms are different between early and late ones? Other than being slightly wider?

DJZ wrote:So the arms are different between early and late ones? Other than being slightly wider?

I believe so, but i can't be sure as I don't have a late model rear arm. but at the end of the day i found a rotor that fit in the space avalible and with a simple spacer it all fits nicely. I am pretty happy with my solution.

Speaking of solutions I have photo's of it all put together.





I have to make a minor adjustment to the hand brake cable bracket and Purchase some longer bolts but otherwise I couldn't be happier