Why brake pad shims - 135is already has them

[Pyrat 2]

I've seen a lot of posts about the titanium brake pad shims. This weekend I performed the F30 backing plate mod and removed my brakes as part of the upgrade. To my surprise the pads already had shims installed on them. Are the shims that everyone is talking about in addition to the shims already installed? Or has the factory started installing these because of the heating issues that have been present since the car was introduced.

[int2str]

Originally Posted by HeelToe

Are the shims that everyone is talking about in addition to the shims already installed?

If you mean the clip-on backing plates, they have always been there.

Titanium shims are less thermally conductive and keep heat away from the pistons and seals.

[WillisW555]

So if I'm going to track my car, I should get titanium shims?

I'll have to read up on this upgrade.

[Pyrat 2]

So the shims are on top of these backing plates or replaces them? This is my 5th bimmer (e36, 2 x e46, e90, and now e82) and this is the first I've seen these. Additionally, I haven't seen them on other cars I've owned. Just curious.

[PeteA]

Titanium shims are a means of insulating the high levels of heat generated by braking into the caliper piston rings.

A particular weak point of the 135i front brakes is that the ceramic piston rings crack under extreme circumstances (track work). Adding a Titanium shim between the brake pad and the caliper insulates the heat transfer and provides additional protection.

The front pads have a backing plate, but no shim by default. The rears have a backing plate + a shim by default (I think a stainless steel one). I have titanium shims from hard braking on my front brakes as well as F30 cooling shields to allow for better airflow to the discs.

[int2str]

Originally Posted by HeelToe

So the shims are on top of these backing plates or replaces them?

They are used in addition to the standard backing plates.

[dcaron9999]

Im about to order the Titanium shims from HardBrakes.com from my "new to me" 2011 135i , but Im on the fence about getting the 05.mm versus the 1mm, versus 2 sets of 0.5mm to be able to stack them.

Are the 0.5mm shims enough to shield enough heat generated by 20 minute lapping sessions? Will the thinner models warp or "burn out" eventually?

Thanks.

[dcaron9999]

What are your thoughts on effectiveness of Titanium Brake Heat Shields versus stainless steel piston kits for occasional lapping/tracking with the BMW 135i?

It is true that the shims can produce a softer pedal?

See product info here:
#1 - Heat shields @ $85 for front calipers:
http://hardbrakes.com/index.php?main...f5668fe8135aae

#2 - Piston Kit @ $360 for front calipers:
http://www.racingbrake.com/Piston-Ki...W-p/bb-61p.htm