Brakes

Not all brake kits for the MR2 are created equally! 

Many other kits on the market for utilize 323mm (12.72") rotors off of the Supra and RX8, and while these are an economical solution, at 21 lb for the front and 18 lb for the rear, the rotors are HEAVY.  The Wilhelm Raceworks kits improve braking performance, without adding extra weight! 

Built around two piece 12.19" rotors, the Wilhelm Raceworks heavy duty kit saves 7-8lb per corner  (~30lb total) compared to a kit based on Supra / RX8 rotors.  The rotors are each about 3lb lighter than stock 93+ MR2 Turbo rotors.  The calipers save ~14lb compared to stock calipers, making the complete brake system weight nearly identical to 91 MR2 Turbo brakes.  Compared to the larger and heavier 93+ Turbo brakes, the heavy duty kit saves about 25lb. 

For a more budget friendly and lighter weight option, Forged Narrow Dynalite calipers and Ultralite rotors save an additional 10lb.  Or mix and match to suite your needs.

The kit uses Wilwood Forged Superlite (FSL) or Forged Narrow Dynalite (FNDL)  four piston calipers for all four corners plus Wilwood MC4 mechanical parking brake calipers.  Removal of the stock rotor dust shields is required.

Made in the USA!

Brake Kit Installed with FSL Calipers

The complete Wilhelm Raceworks Brake Kit consists of the following parts:

• Aluminum caliper brackets, front and rear
• Hardware for attaching the brackets and calipers
• Four custom made Wilhelm Raceworks aluminum rotor hats
• Socket head cap screws and "jet nuts" for attaching rotors to hats
• Steel braided PTFE brake lines front and rear
• Aluminum bracket for parking brake calipers with attachment hardware
• Custom parking brake cables

• Your choice of Wilwood FSL or FNDL calipers
• Choice of Wilwood rotors, blank, slotted, or "ultralite"
• 2x Wilwood MC4 mechanical calipers
• Choice of Wilwood BP10 or BP20 brake pads, or omit the pads if you have another favorite
   

Installation Instructions

Kit with optional FNDL calipers and Ultralite Rotors

For those looking for a more budget friendly and even lighter weight option choose the Wilwood Forged Narrow Dynalite calipers and Wilwood Ultralite rotors.  The calipers and pads are slightly smaller, and the rotors are lighter weight.  Not only does this save you some money, it saves an additional 10 lb off the brake system weight.  Suitable for street, autocross, and occasional track use.  If you are building a serious track car I recommend the FSL calipers and HD or GT rotors.

Notes:

• Beginning July 2019, all brake Wilhelm Raceworks brake kits come with socket head cap screws and Mil-Spec MS21042-5 self locking "jet nuts" for attaching the rotors to the hats.  NO MORE SAFETY WIRE REQUIRED!  If you have an older kit and want to convert to the new attachment I can modify your hats for $10 each, plus $10 per rotor for the new hardware kit.

• The Wilwood BP20 pads will handle quite a lot of track abuse in my experience, but they can be a little noisy when cold.  The BP10 is more street friendly.  Other pads are also available.  Please contact me if you wish to discuss substituting alternate pads.
• For those looking for extra front wheel clearance, I can also substitute the thinner rear rotors and hats for the normal fronts, along with a narrower front caliper.  This will save you ~0.44in (11mm) of caliper to spoke clearance.  Please leave me a note in the checkout if you would like this option (cost is the same as a normal front kit)
• The standard calipers included in the complete kit provide a moderately conservative brake bias with the NA proportioning valve, and a more aggressive bias with the Turbo valve.  If you have an adjustable proportioning valve, larger rear calipers will provide better overall bias. Feel free to contact me if you wish to discuss brake bias in more detail.
• Red or black powder coated calipers are special order items and will take an extra 3-4 weeks to deliver.
• The calipers, rotors, and pads ship directly from a distributor and will arrive separately from the rest of the parts.
• The calipers available for this kit do not include dust seals.  This can be a problem for passing inspections in some locations.
• The HD or GT rotors are generally recommended for heavy track use.  The Ultralite rotors will work, but may need to be replaced more frequently.
• The Forged Narrow Dynalite caliper is unique among Wilwood calipers in that it has a raised logo, and when ordered with powder coating the logo is not laser engraved.  If you would prefer the silver logo like other Wilwood calipers chose the machined logo option.  Otherwise the raised logo will be the same color as the rest of the caliper.  Gray anodized calipers will come with the machined silver logo as shown in the pictures.

StopTech Big Brake Kit

The ultimate MR2 brake kit!  Replaces the Wilwood calipers with Stoptech's ST-43 Race caliper for industry leading caliper stiffness, plus staggered pistons to combat pad taper wear.  Additionally, the piston sizes are specifically chosen to optimize brake bias for the MKII MR2.  You won't find these calipers anywhere else!

The complete Wilhelm Raceworks StopTech Brake Kit consists of the following parts:

• Wilhelm Raceworks aluminum caliper brackets, front and rear
• Hardware for attaching the brackets and calipers
• Four Wilhelm Raceworks aluminum rotor hats
• Socket head cap screws and "jet nuts" for attaching rotors to hats
• Techna-Fit Steel braided brake lines front and rear
• Aluminum bracket for parking brake calipers with attachment hardware
• Custom parking brake cables

• 2x StopTech ST43 Race front calipers
  • 30mm/34mm staggered pistons for stock NA or adjustable proportioning valve
  • 34mm/38mm staggered pistons for stock Turbo proportioning valve
• 2x StopTech ST43 Race rear calipers 
  • 26mm/28mm staggered pistons
• 2x Wilwood MC4 mechanical calipers
• Choice of Wilwood rotors, blank, slotted, or "ultralite"
• StopTech Sport brake pads, suitable for street and moderate track use (other pads available on request)

Adjustable proportioning valve kit available here.

Installation Instructions 

Notes:

• The StopTech calipers in this kit are made to order.  Lead time has been longer than normal recently, as much as 6 months in some cases.
• The calipers included in this kit do not include dust seals.  This can be a problem for passing inspections in some locations.
• If you have a favorite brand of brake pads you wish to use, the pads can be eliminated from the kit, or an alternate pad can be substituted.  Please contact me to submit a custom order if you would like pads other than the standard StopTech Sport pad.

Basic Big Brake Kit

If you prefer to purchase the rotors, calipers, and pads yourself, the basic kit contains all of the custom parts of the kit.

To complete your brake setup you will also need to purchase or already have:

• 2x Wilwood FSL or FNDL calipers for front
• 2x Wilwood FSL of FNDL calipers for rear
• 2x Wilwood MC4 mechanical calipers
• 2x 12.19" x 1.25" rotors with 8x7.00" bolt pattern
• 2x 12.19" x .81" rotors with 8x7.00" bolt pattern
• 2x Brake pad set for your choice of calipers

Installation Instructions

Technical Info

Rotors

This kit can use virtually any 12.19" rotor with an 8x7.00" bolt pattern, 1.25" thickness for the front and .81" thickness for the rear.  There are numerous options from various manufacturers including Wilwood, Afco, Colman Racing, and many others.  They are available with straight or curved vanes, and slotted, cross drilled, or both.  The Wilwood options are shown in the chart below.  There are many others on the market as well.  Be sure to purchase one right and one left if buying curved vane rotors!

Calipers

Caliper choice is important to optimize brake bias for maximum braking potential, while minimizing the chance of locking the rear brakes before the fronts.

For MR2s equipped with the non-turbo brake proportioning valve, the standard 1.38" / 1.12" calipers provide a slightly conservative bias.

For those with the turbo proportioning valve the 1.38" / 1.12" caliper combination will provide optimal bias at about 1g deceleration.  High grip race tires and high friction pads may require an adjustable proportioning valve, or a swap to the non-turbo proportioning valve.

When an adjustable proportioning valve is used, increasing the rear piston size to 1.25" will produce better bias over a wider range of deceleration rates.

More details on brake bias and the effects of various caliper / pad / proportioning valve combinations can be found on my Brake Bias page.  Please contact me if you have questions about choosing calipers for your setup.  Note: FSL = Forged Superlite, FNDL = Forged Narrow Dynalite

Another caliper option is to use the 1.62" calipers in the front, paired with either the 1.38" or the 1.25" in the rear.  The 1.25" piston setup is a bit more conservative than the setup above, but should provide good performance.  It will also reduce overall brake system pressure.  An adjustable proportioning valve is recommended for the 1.38" rear option.  This may also be an option for those who already have a set of calipers they want to use.  Part numbers for this option are listed below.

The parking caliper used with the kit is the Wilwood MC4.   One of each LH/RH is required.

The part numbers above are the black powdercoated version.  Red and silver are also available.
 

Brake Pads

Many companies make pads in many different compounds for the Wilwood FSL caliper, including but not limited to: Wilwood, Stoptech, Porterfield, Performance Friction, Hawk, Raybestos, etc.  The Wilwood pad shape for the FSL calipers or the Stoptech ST43 is #7420, and for the FNDL is #7816.

Custom Parts

The Wilhelm Raceworks hats and main caliper brackets in this kit are machined from 6061-T6 aluminum, and black anodized.  All are designed around the brake torque required for 1.4g deceleration, and with a factor of safety of 2x on the 500 million cycle fatigue strength of 6061-T6 aluminum.

The parking brake system in these kits is capable of achieving deceleration rates of ~.3g.  More than enough to pass the emergency brake function tests that I am aware of.  However, it is ultimately designed and intended to be a parking brake, or for that once-in-a-lifetime emergency situation.  If you are drifting or doing hand-brake turns, you may find it to be insufficient.

Assuming adequate spoke to caliper clearance, most 16" wheels should fit over the front brakes without issue.  The parking caliper in the rear might cause an issue with some 16" wheels.  Use the template below to check fit on your wheels before ordering.

Caliper Clearance Template for HD Brake Kit

Caliper Clearance Template for Ultralite Brake Kit

Caliper Clearance Template for Stoptech Brake Kit