Recommended for racing conditions only - this is the ultimate in racing brake fluid!
- · Wet Boiling Point 270C / 518F
- · Dry Boiling Point 310C / 590F
- · Available as 12-pack cases of 1 Litre Bottles
Castrol SRF Racing Brake Fluid is an ultra high performance product formulated specifically to satisfy the ever increasing stresses placed upon the braking systems used in international motorsport.
Castrol SRF is less hygroscopic than conventional brake fluids - it absorbs less water in a given time.
Secondly, unlike conventional glycol ether fluids, Castrol SRF reacts chemically with the absorbed water to reduce its adverse effects, thus preventing the fluid's high temperature performance and safety margins from deteriorating as rapidly as they would otherwise do.
It's ability to withstand temperatures in excess of 300 C, and its superior resistance to the effects of absorbed water, have established Castrol SRF as the world's premier fluid for the hydraulic brakes used in all forms of motorsport.
TECHNICAL NOTE: Mixing Castrol SRF and conventional brake fluids will reduce the benefits of Castrol SRF.
It is strongly recommended that conventional brake fluid be drained from the system before flushing and re-filling with Castrol SRF.
SmarTemp Temperature Strips
- · For measuring temperatures of calipers and other components (heat exchanges, transmissions, and differentials)
- · Used by top race teams worldwide in testing and race conditions
- · Provides excellent feedback for fleet maintenance managers
- · Easy to use, easy to read - color changes to black when rating exceeded
- · Temperature ranges from 250 degrees (use symbol) F to 536 degrees F (121 degrees C to 280 degrees C)
- · Available in packs of 10 strips
General Information about Brake Fluid
Brake fluid is hydroscopic (absorbs water). When fresh from the can, it can be considered "dry" with the higher boiling point.
That's why racers and people doing driver's schools change the brake fluid just before events.
Over time, brake fluid absorbs water lowering its boiling point to the "wet" level.
Brake fluids improperly packaged in a plastic bottle can take on moisture while still on the store shelf.
Performance Friction offers two brake fluids, both packaged especially to protect the fluid from excess moisture while on the shelf.
For street cars, wet boiling point numbers are more important than dry because the fluid stays in your car for quite a while (one to two years).
After a few months, with exposure to humid air, the brake fluid performance is probably closer to the wet than dry point.
Brake Fluid Recommendations
Brake fluid is one of the most overlooked aspects of brake system maintenance - but needs to be changed more frequently than most people think for two reasons, maintenance and performance.
It generally takes about a quart to flush the system.
Changing old brake fluid removes water from the brake system. Brake fluid is hydroscopic, it absorbs water.
Old brake fluid must be flushed out or water absorbed by the fluid eventually causes internal rust on the disk calipers and pistons.
Changing old brake fluid helps high temperature operation because fresh (dry) brake fluid has a higher boiling point than older (wet) brake fluid.
If brake fluid boils, compressible gas bubbles form, resulting in a very spongy brake pedal.
Normal or Fleet Applications - Use a high quality fluid such as Z-Rated® that comes in a metal container and meets DOT requirements.
Change with every brake job or every six months to one year - whichever comes first - to provide the maximimum stopping power and avoid that mushy pedal feel.
Competition (motorsport) Applications - Change your Z-Rated® or Castrol SRF before every race.
DOT Specifications:
|
|
DOT 3 |
DOT 4 |
DOT 5 |
|
Dry Boiling Point |
401F |
446F |
500F |
|
Wet Boiling Point |
284F |
311F |
356F |
The DOT 3 and DOT 4 specifications are for glycol based (regular) brake fluid, while DOT 5 is for silicone.
Silicone DOT 5 is not compatible with the ABS hydraulic control unit because it doesn't lubricate the ABS pump like glycol based fluid.
Silicone is slightly more compressible than glycol fluid.
It has a higher wet boiling point because it doesn't absorb moisture like glycol fluid.
This lack of moisture absorption causes problems when water gets in the brake system.
Instead of mixing with the brake fluid (so it can be flushed out easily), the moisture gets trapped at low points in the system and causes rust.



