Drilled VS Slotted Brake Rotors– Understanding the Difference in Performance and Design

Upgrading the braking system on your car is by far one of the best ways to improve its performance. Being able to brake hard with confidence is key both on and off the track. As far as brake upgrades go, getting a set of aftermarket brake discs is one of the most popular routes enthusiasts take.

However, there are various choices you can make when it comes to this particular braking component.

There are drilled and slotted rotors available that promise to boost your car’s braking power.

The question is, which of these is the better choice? In order to answer that question, we’ll have to dive deep into the inner workings of modern braking systems.

Don’t worry, though. By the end of this guide, you’ll have all the information you could need to make the right choice for your particular car.  

Understanding the Physics of Brake Rotors

Disc brake rotors are found on the majority of modern cars. Some come with only front discs while others feature all four. Even though using friction pads on cast-iron discs is a technology invented all the way back in 1929, it took the automotive industry a long time to realize that this method of braking is simply superior. We’ve only seen the wide use of brake discs on cars since several decades ago.

Solid brake discs worked wonders for a while. However, as vehicles became larger, faster and heavier, the industry noticed a number of issues that had to be fixed going forward.

Heat is the number one enemy of any braking system. Brake too hard and you’ll quickly experience brake fade. Brake fade is a phenomenon where you lose braking power either suddenly or overtime.

This happens when the braking system is under high stress for prolonged periods of time. Solid rotors, although great for economical commuting, don’t really do well in terms of heat and brake fade mitigation.

Adding Ventilation Cavities

Brembo Ventilated Rotor

One of the initial solutions was to go with vented discs. Vented brake discs have a cavity between the front and rear braking surface, which allows cool air to pass between them during braking. Having that extra airflow helps mitigate the heat and drive it away from the rotor itself.

At this moment, ventilated solid-surface discs like our Brembo UV Coated line of ventilated discs, are still one of the best solutions out there. However, heat is not the only enemy you’ll face when trying to improve your braking system.

Mitigating the Build Up of Gasses

As brake pads come into contact with brake discs, they start to produce small amounts of residual gasses.

When the pads heat up under hard braking, they’ll release just enough gas that gets stuck between the pad itself and the rotor. Since they’re no longer able to grip the disc surface effectively, the pads start to exhibit brake fade.

Drilled Brake Rotors – A Simple and Elegant Solution

Brembo Xtra Drilled Rotors

If you have a layer of gas between the rotor and the pad, what’s the most logical way to get rid of it? Drilling some holes into the disc surface.

Drilled discs were a real breakthrough back in the day. Just like brake discs in general, drilled ones have been used for a long time. The real question is, how well do these hold up today?

Drilled brake discs have their benefits. A good, drilled rotor will bring these benefits to the table:

  • Improved Fading Resistance – As mentioned before, drilled discs are great at keeping those residual gasses away from the disc. This is still one of the best reasons to get drilled discs.
  • Improved Temperature Mitigation – Having additional routes where air can circulate through the disc means that you’re getting better cooling of the entire system.
  • Aesthetics – Last but not least, drilled discs simply look good. There’s nothing better than combining a beefy drilled disc with a set of large calipers and a good looking wheel.

There are also a few potential negatives worth factoring in when you’re dealing with drilled discs. By drilling the holes in the disc, you’re slightly reducing its integrity. Our manufacturing processes have countered this effect to a great extent. We’re now offering some of the best drilled discs on the market, such as the Brembo Xtra series.

However, drilled rotors are not the only solution for sporty driving. We also offer a complete line of slotted brake discs.

Slotted Brake Discs – The High-Performance Solution

Brembo Slotted Rotor

Thanks to the high quality of modern braking compounds, there was a significant reduction of residual gasses that formed between the pad and the disc.

As cars got faster and heavier, we started seeing much higher temperatures generated on brake discs under full load.

Just like drilled discs, slotted discs were invented to further reduce the impact of brake fading. Instead of using holes, slotted discs have grooves that run along the surface of the disc.

These channels serve several purposes.

  • Improved Pad Grip – Every time a brake pad goes over the grooves, it loses a very small layer of braking compound. We’re talking reduction at the atomic level. By losing some of its material, the pad is offering a better overall grip. This, in turn, boosts your braking power.
  • Gas and Debris Mitigation – Despite not having actual holes, slotted discs are every bit as good at mitigating whatever residual gasses you might run into with modern brake pad compounds. The same goes for dust and any other type of debris that might impair your braking system’s ability to function efficiently.

Whether you choose our drilled or slotted discs, you are guaranteed to improve the overall efficiency and performance of your braking system.

Start with the Right Brake Pad

An often overlooked aspect of upgrading your brakes is choosing the right pad. Investing in a good set of brake pads will give you a serious boost in braking power even if you’re running stock discs.

This effect is only compounded when you add quality made Brembo rotors to the equation.

Because of that, make sure that you have the right braking compound gripping your new set of discs.