Hi All,

Long story short, doing the Nissan 4 pot caliper conversion on my ma70 Supra.

To do the mod I need the 30mm caliper, but I have accidently purchased the 26mm caliper.

I'm going down the route of putting in a 5mm spacer to make the 30mm rotors I have in mind fit. (thanks Norbie for the info)
Now lets ignore the price and time vs buying the correct caliper debate please.

I have the following questions, I know cool1 has done this: http://www.toymods.net/forums/showthread.php?t=4182 and I have PM'd him for more info, but in the meantime :

1. What would be a good compound metal to use for the shim, seeing as the caliper gets very hot and will most likely warp the spacer if a low grade material is used. It has been suggested in the other thread that it should have a "similar thermal expansion coefficient" to the caliper. Anyone know the "thermal expansion coefficient" of the sumitomo aluminuim calipers?

2. When you split the 2 caliper halfs, one side is flat where the hole for the brake fluid is, and the other side has a 2mm recess with an o-ring in between which sits flush in the recess. When making the spacer, should I just make the spacer flat, or should I make one side falt and the other with a small recess, and have 2 O-rings (the original and the one that sits in the spacer)?

3. Should I use a special type of O-ring? I know brake fluid can be pretty nasty on paint, so I assume it would eat through some rubber\plastics?!

Thanks in advance

Sam