MRT on Disc Brake Rotors

MRT Performance is proud to offer the proven performance and durability of slotted and OR drilled rotors. These are the best rotors we've found for high performance street use in a WRX.

Products are available for immediate purchase on-line at the MRT-Shop. Hundreds of items with photos available now. Both Australian and International shipping is no problem.

These rotors are direct, bolt on replacements for the standard parts, and come in MY94 - 98 (ver 1 2 3 4) and MY99 (Ver 5) [4 spot STi caliper type] sizes. The main benefits of these parts are superior performance and improved looks.

On the slotted rotors, directional slots have been milled into the rotor surface.

These slots have two benefits. Firstly, they lightly scrape the brake pad during use, preventing glazing of the pads, keeping performance at 100%. Secondly, they aid in dispersion of dirt the gasses emitted by the pads under hard use ("out-gassing"), keeping the pads in constant contact with the rotors.

For ultimate performance and looks MRT Performance recommends the slotted and drilled rotor.

These top of the line rotors have been designed, utilising advanced computer modelling. As well as the slotting described above, the rotor is also cross-drilled (see picture). The carefully designed holes (one per vane on ventilated front discs) aid cooling of the rotor, as well as dispersion of water, dirt and out-gassing.

Read a Customers Comment

In an independent test, these rotors gave a 5% shorter stopping distance over OEM parts. The rotors were the only change. The testers, from the Nationwide Defensive Driving School, also reported greater consistency in brake operation and improved pedal feel. Now you know: those holes and slots aren't for show!

As befits a top of the line product, the rotors are plated with a gold coloured zinc di-chromate passivate on non-wearing surfaces. This plating inhibits surface rust and enhances appearance with a high-tech, two-tone look.

Made in Australia, these parts are reasonably priced. Even the top of the line Drilled and slotted rotor is cheaper than the standard part.

A Word on Motorsport Use

The WRX is a great car to punt hard. Sensibly, many owners are taking to the track to enjoy their cars in a safe and legal environment. Unfortunately, these 'Track Days' represent the hardest possible use for your car's brakes - even harder than true racing! Your brakes' enemy is heat and the effect of rapid temperature change. Race teams know this and go to extreme lengths to bed in, then warm up and cool down brakes before and after each race. Most likely disc rotors will be replaced after each race.

In contrast the usual practice at a 'Track Day' is to wait your turn, do a few very hard laps then come off to let the next bloke have a go. This gives your car's brakes no time to warm up or cool down. The brakes are expected to tolerate this, with minimum maintenance, for years. In fact, over time this behaviour is likely to cause cracking in the disc rotor, no matter how good the quality of the part. Cast iron just doesn't like to be constantly expanding and contracted rapidly.

With this in mind slotted only rotors are more durable, however not as good as the drilled and slotted.

Other Recommendations

If you plan to do a considerable amount of track time in your WRX, MRT Performance also recommends a switch to a set of racing brakes, such as Brembo. These will solve most problems. However they are costly (you get what you pay for) and may require de-activation of your ABS.

With all high performance brakes we recommend PAGID road or race brake pads plus a simple upgrade to the master cylinder ( probably the cheapest upgrade you can do to your car) AND Stainless steel brakes lines.

See details on bedding in and general brake maintenance.

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