| GSpeed |
08-19-2015 06:51 PM |
TESTED- Perrin Master Cylinder Brace
We had a spare analog input, a spare shock pot, a Perrin master cylinder brace, and some time to kill. Let's find out if it actually works!
First thing we did was mount a shock pot horizontally in line with the master cylinder:
http://i.imgur.com/OqKAQjV.jpg
Interestingly enough, we had marginal deflection. On the order of a few thousandths of an inch. Watching it, we noticed the master cylinder was actually deflecting upwards, not forward like you'd think. It rotates around a point on the firewall, roughly, so that the end is pushed upwards. So we got a little creative with some machining measurement fixtures, and wound up with this:
http://i.imgur.com/YTmhUyS.jpg
Despite the angle of the picture, the shock pot was perfectly vertical and in line with the front face of the master cylinder. Once we had that setup, we definitely recorded some deflection.
The tests were performed with the engine off (no vacuum assist). The brake pedal was pressed several times at varying pressure. Brake line pressure was monitored via OBD2 at a resolution of 1 bar (14.7 psi), and the master cylinder deflection was measured via analog channel at a resolution of 0.001" (4 inch linear potentiometer at 12 bit resolution).
http://i.imgur.com/HV5hxQQ.jpg
You can see here, despite what may be a structurally inefficient position, it's absolutely effective, reducing master cylinder deflection by 57%. Could it be better? Maybe, but the returns would be minimal. You guys already know it improves feel, here's why. |
