James Z31 Engine Blueprinting

[DJZ]

My mate has used Spray Store before, said they were pretty good.

[nick_m]

yeah spray store would be my pick too

[85_Z31]

yeah spray store would be my pick too

Cheers Guys

I will give them a call when i get back From down South ( leaving in couple days time )

and Nick, as you can see i just gave it death with the welder and it came up mint, i probally had to do a lot more grinding and filling than you would have had to, but i think the end result is tidy enough.

[nick_m]

yeah dude looks good, don't know what you needed me for

[85_Z31]

Of course you guys remember that I casually nailed on some 4 Pot Front Brakes a little while ago

so now its time to convert the rear end from 290x10mm ( solid ) to 290x20 Vented

Of all things I reckon a Jaguar Rotor is going to be a way to go because i can't find any other rotor with a low enough offset
( so that the rotor doesn't hit the caliper )

jag rotor.png

So i think its time to bust out the cardboard and the Glue to make a "Mock up" life size section of the rotor to check Fitment Before I Drop $220 on parts I can't use.

[85_Z31]

Been out to do some measuring

OD of Rear Hub is 154.8 - 155mm
you zoom in you can read the measurement , so that definitely fit inside the Jag Quoted measurement of 159mm

Measuring Between the Pad Carrier i get 24mm


Using a straight edge the face of the Hub to the Edge of the pad Carrier is 43mm


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.

It would be Idea to use a rotor with slightly more offset , but it seems to get a rotor with under 42mm total height is extremly rare as most of the 2mm vented rotors use a total height of 57mmto 80mm

[nick_m]

possibly stupid queston but did you check out the DBA Catalog, i've always found that useful for rotor hunting

[DJZ]

You can't use factory late Z31 rotors?

[85_Z31]

You can't use factory late Z31 rotors?

late Style Z31 Rotors have a total height of 57mm ,

this is what happens with the early style rotor that have a total height of 47mm



the DBA catalouge was helpful, but the Brembo Catalouge in most cases shows a full drawing with better detail of the same rotor.

[DJZ]

Sorry, reading this on a cellphone hah.

So you are using late Z31 calipers? What's the reasosn why the rotors to match don't work? I know the control arms and companion flanges are longer, are the caliper mounts in a different place?