Endless Racing MONO4 Front Performance Brake System for GDB Subaru Impreza WRX STi



Endless Racing MONO4 Front Performance Brake System for GDB Subaru Impreza WRX STi

STOCK STATUS: Special Order
These items are typically not in stock and either made-to-order or special order from the manufacturer. After you order we will confirm the estimated lead time and other order details. If you have a specific deadline to receive this order please talk to us before placing your order to ensure that the manufacturer can meet your expectations.
Guaranteed Safe Checkout
Payment Options - American Express, Discover, Visa, MasterCard, JCB, Maestro Credit Cards Payment Options - Apple Pay, PayPal, Splitit, Dinser Club International, Union Pay Credit Cards
Additional Info
Shipping policy

Endless Racing MONO4 Front Performance Brake System for GDB Subaru Impreza WRX STi

4POT caliper version of forged and molded Monobloc Calipers. Conducting many tests in pursuit of reduced weight, durability, radiation, etc., Endless reviewed the shape of the details time and again before achieving perfection. They also enabled installation of wheels from 15 inches as well as increasing installable wheels.


  • Weight : 2100g
  • Size : 141mm x 72.5mm x 270mm
  • Compatible Rotor Diameter : φ300mm – φ355mm
  • Std Color of Kit : Racing Anodize
  • Std Compound for Kit : Type R / MX72 / MX72-Plus
  • Compatible Wheel Size : 15″

For racing, rally or street, Endless only uses the highest quality materials and design to achieve the best performance possible. These calipers will cope in the toughest of conditions without flexing or losing accuracy. Combine the calipers with RF650 Racing Super Fluid for optimum performance. Your pads will be applied and released with great precision and reliability.

Forged Monobloc Caliper Body

Monobloc Calipers forged and molded through several thousand tons of pressure. 4 years after its conception and 1 year after the completed prototype it was entered into test races repeatedly and changed its specifications while also obtaining a body that is sufficiently light and hard to compete in races. The processing of the highly difficult piston cylinder was cleared using advanced special technology. The finished body was completed using an ultra-hard anodized aluminum. It is the final product of the technology created by Endless and its “never-ending challenge” as it continues to focus on quality forging.

“E-Slit” Double Shaving Effect

The long slit which draws gentle curves and the E slit which runs above the long slit are what make E-Slit Rotor impressive. The pad is constantly kept in optimal shape through the double shading effect demonstrated by the long slit, which gently carves the pad, and the E Slit, which gives strong brake force, providing further improvement of brake force. When the long slit on the rotor surface side disappears and the letter E floats up it is about time for replacement.

Also, even during the period of use, the brake rotor may be damaged due to aging deterioration such as rust and corrosion, so it is recommended to replace it at least once every two years.


  • Material : Steel with Special Carbon
  • 1-Piece Design
  • Slit Shape : E-Slit
  • Special Heat Treatment


  • The E-Slit rotor consists of the narrow curved slit incorporated with 4 smaller E-Slits. The smoother shaving of the pad by the long curved slit and the increased friction provided by the E-Slits maintain optimal brake pad condition at all times. The rotor material consists of a special carbon blend, an Endless original technology, facilitating stable mu-levels, decreasing heat cracks and extracting 100% of the brake pads performance. Slits are designed for optimal shaving.

Cost Effective, and More On So Many Levels

  • Endless Steel discs are more cost effective, and offer a wider range of performance options. Many drivers and racing teams prefer the feel and characteristics of Endless steel discs.

Special Heat Treatment Process

  • With prolonged hard driving, the rotor surface will expand and contract due to heat, causing fine cracks (heat cracks), and you will not be able to obtain appropriate friction. To prevent this, special heat treatment was performed in advance to stabilize the components of the rotor itself and significantly reduce heat cracks during hard driving. As a result, the life of the rotor has been extended, and it has become possible to use it for a long time with peace of mind.

Blue Rotor Hat Finish

  • The bell hat part is painted blue to aid in preventing corrosion resistance and also can be expected to have a dress-up effect.

Ultra-Hard Alumite Caliper Body

Ultra-hard alumite is used for the caliper body of our monoblock series. A tough ram coat is used for the rotor bell housing. This makes it possible to significantly delay the discoloration of alumite even when used under high temperature conditions when driving on a circuit.

Hard Anodized Finish

The finish is a hard anodizing, which is the preference under track conditions. When raw aluminum reacts with the oxygen in the air, a hard surface film develops on aluminum which prevents further degradation. The process is called oxidation, and you can think of it like rust. The anodizing process leverages this natural phenomenon, and takes it a step further to produce an extremely hard protective layer of aluminum oxide. The result is a finish that is far more appropriate for racetrack use. Anodizing creates a uniform surface that is much more abrasion resistant than paint or powder coat.

About Bedding

Circuit-dedicated pads that emphasize high-temperature characteristics, in order to bring out the original performance, it is indispensable to perform the work called “bedding” in which heat is applied in advance before hard driving to make a hit.

Bedding is always done in the top categories SUPER GT, WRC and various races in Europe.

Before using semi-metal brake pads, proper bedding is required to stabilize high temperature performance and extend the life of the pads and rotors.

How to Bed

  • When driving on a circuit when a new product is installed, raise the rotor temperature to about 400 – 500° C while avoiding hard braking, and add atari. After that, if the temperature is lowered to 100° C or less by natural cooling, the process is completed.

Kit Contents

  • Endless Racing Calipers (2)
  • Brake Pad Set
  • Caliper Mounting Brackets (2)
  • Large Diameter Brake Rotors (2) – 332mm x 30mm 3PC
  • Stainless Brake Lines (2)

Fitment Details

  • Fits Applied A / B / C / D


  • It may not be possible to bring out the original performance of the brake pads when bedding in the rain. Bedding should be done in fine weather as much as possible.
  • Compatible wheels vary depending on the wheel brand and size.
  • This product uses an E-slit rotor.
  • Please note that there is no custom color setting for the Racing Monobloc series.
The Bulletproof Automotive website contains many thousands of products purchased in multiple different currencies. All of the prices are entered manually and accurately at the time of entry. Due to the consistently fluctuating international exchange rates, at times prices may not be able to be honored at their original intended rate. We apologize for any inconvenience this may cause, unfortunately our website is unable to compensate dynamically for what can at times be volatile changes in the cost of items due to currency values fluctuating, changes in prices from suppliers, changes in shipping and import duties, and other factors. Rest assured that any order you place on line will be at zero risk to you in this area. If in the event your order cannot be fulfilled at the original intended website price we will offer you a 100% refund, no questions asked. We will continue to do our best to maintain updated prices and we will always continue to offer our price match guarantees as well to ensure our prices are always the best for you. In short, prices may change without notice. It is always advised to give us a call prior to placing your order online to confirm availability and to confirm current pricing.
Items that are in stock in the US, either at Bulletproof’s warehouse or at a supplier’s warehouse, are generally delivered within 7-10 days. Special order items from overseas take considerably longer. As a courtesy Bulletproof offers delivery estimates to our customers which take into consideration manufacturer availability and shipping schedule. These estimates represent our best guess based on previous orders from the manufacturer and do not in any way imply a guaranteed delivery window. Many manufacturers work in a “just in time” inventory system and often take 2-20+ weeks to produce an item once an order is submitted. All deliverable items are then sent to our Japanese warehouse. Bulletproof ships a minimum of one full ocean freight container every month from Japan, oftentimes more than one a month. Ocean freight takes an average of 4 weeks. Typically it breaks down to one week in Japan for paperwork and customs, two weeks by boat and one week in US customs/clearance. Due to the wide number of variables between manufacturer and shipping schedules, delivery estimates are simply just that – estimates. We attempt to estimate conservatively and we usually deliver faster than our estimates suggest. It is not Bulletproof’s policy to guarantee delivery time of any special order item, this is impossible for us to do. By ordering you acknowledge that there is no required delivery ETA and an order may not be canceled or altered due to manufacturing or shipping delays, all ETA’s are provided as a best guess only. Please review the full Terms & Conditions here.
We do pricing a little differently on our JDM brands and we believe in making things simple and clear. No hidden fees or surcharges. Every price you see includes the shipping cost to our office in Los Angeles, California and all the associated taxes/duties/fees for bringing the products into the US. The only shipping you ever pay is from our facility in the US to your location. Be wary of resellers that don’t include the cost of international shipping in their pricing on JDM parts. While we believe we’ll always have the lowest all-in price on JDM products, we offer a price match guarantee for all authentic parts purchased from authorized dealers as well. For many international customers, it’s much more affordable to ship from the USA than from Japan directly, as the air freight and ocean freight costs are typically much less. However, for customers looking to ship directly from Japan outside of North America, or domestically in Japan, we can provide pricing specifically for that scenario. Please do not hesitate to contact us with any pricing questions or concerns. Please email us at sales@bulletproofautomotive.com with any inquiries.


There are no reviews yet.

Only logged in customers who have purchased this product may leave a review.

Stay up to date with the latest product releases, Bulletproof Automotive builds and more. Sign up for our newsletter to receive the most up to date information in the aftermarket tuning world, and bring your build to a whole new level.