Brake Master Cylinder Heat Shield

So you upgraded your calipers, master cylinder, lines, and pads expecting your car to be able to handle the increased power. Driving around town they feel great and you can really feel the improvements. When you hit the track, something else happens. You’re heading down the straight over 130mph and when you go to hit the brakes into turn one your pedal just falls to the floor and your speed is not decreasing rapidly enough…

This is not the situation you want to find yourself in, and it’s not the appropriate time to be going over your checklist – did I bleed the brakes properly, are my brakes overheating, did a hose or line come loose?

If you’re like me and went with a top mounted turbo but you did nothing to shield the heat of that turbo from your brake master cylinder then you should probably read on before you find yourself in a situation where you may end up off track or worse, in a wall.

Very simply, the exhaust housing of the turbo gets really hot under normal use and extremely hot when doing lap after lap in the middle of the summer on a road course. If you don’t have a turbo blanket or ceramic coating on the housing then all of that heat is hanging out in the engine bay and saturating surrounding components. The closest thing in an S14 setup is going to be your brake master cylinder.  You’re basically boiling your brake fluid causing it to compress substantially before actually providing the stopping power to your brakes.

A heat shield is a relatively cheap solution that only takes a few minutes to install. It’s something you can buy online from companies like Circuit Sports or Megan Racing, or you can fabricate your own. I’ve seen some elaborate custom setups using gold plated tape to act as an improved heat reflector. How far you want to take this depends on your needs. Consider this a step in the right direction, but in extreme situations it may not be the final solution. I will be able to report more after my first track day of the season.

The concept here is the heat shield is a metal partition that separates the BMC from the turbo and downpipe. The heat is reflected off of the metal and does not get absorbed as easily into the BMC. The one I purchased was designed for an S13 but is easily adjusted to work with an S14. It simply bolts on to one of the BMC bolts, and the other one went where I believe my original power steering pump would have mounted. Two of three holes matched up on the S14 without any adjustments required. However, I did bend and hammer one of my corners down to get it off of and away from my downpipe. I also bent one of the top edges outward a bit to give extra clearance from my brake lines. I didn’t want the metal rubbing or touching for safety reasons and to allow the shield to do it’s job properly.

This installation took me less than 15 minutes, including my adjustments and I highly recommend it for those of you who do any serious driving in your modified S14.

The turbo is too close to the unprotected brake master cylinder
The turbo is too close to the unprotected brake master cylinder
An inexpensive heat shield will help protect the BMC
An inexpensive heat shield will help protect the BMC
A test fitting shows the heat shield will bolt up fine, but it touches the downpipe
A test fitting shows the heat shield will bolt up fine, but it touches the downpipe
closeup of the heat shield touching the downpipe
closeup of the heat shield touching the downpipe
I marked the shield and bent and hammered it to avoid touching the downpipe
I marked the shield and bent and hammered it to avoid touching the downpipe
I pulled the shield outward at the top, away from the brake lines
I pulled the shield outward at the top, away from the brake lines

3 thoughts on “Brake Master Cylinder Heat Shield”

  1. Happy to report that the heat shield worked great on the track (combined with a new PTP Turbo Blanket). No brake fade at all!

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