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Wow, who would have thought that one little system of the car could cause SO much trouble? Ok, well I'll be the first to admit that the brakes are more than just a "little system" but I'll also be the first to admit that they can give you a world of headaches!!! This one sub page will try and hold all the AW11 brake info in one place. In this section you will find info on the following: Maintenance:
Upgrades:
Warped Brake Rotors This is a common problem for any "spirited" driver no matter what the year, but even more of a problem for even the more conservative driver of the 85 and 86 model year cars. Some consider the brakes that were put on the car during these two years to be a tad undersized, thus making them easy to overheat and warp. First thing to check is to make sure that your caliper is not sticking. If so, look further down on info on how to rebuild brake calipers. While proper care of new rotors will increase life dramatically (allow cool off between high speed stops, don't splash with cold water, don't put on parking brake if brakes have just been used hard, etc.), some will still warp a new set in short time due to harsh driving. However, if you have an 85 or 86, there is an alternative, that being the 87+ brake upgrade. Look below for info. Finally, if you are just looking for options on what to replace your worn out rotors with, check out the brake upgrades section on rotors below.
85-86 to 87+ Upgrade After complaints from customers prematurely warping the rotors on their 85-86 cars, Toyota upgraded the brakes in 87. And yes, the larger brakes from the 87+ car can be easily swapped onto an 85-86 car. You only need 2 or 3 things, it depends on what you want to do. For a bare bones swap, all that is really needed is the 87+ rotors and mounting brackets. While the 85-86 and 87+ calipers are different, some people are able to use the older calipers with the upgraded rotors and brackets. The difference between the two is that the 87+ calipers have a larger slot for the brake pads because of the rotor thickness difference. They are also a little beefier in overall width. If you do use the older calipers you may have to shave your new pads, as it will be a tight fit without the extra clearance the 87+ calipers give you. If you want to go the whole way, you will need the 87+ dust shields. Since most people are upgrading after warping their rotors anyway, the only unique parts needed are the 87 mounting brackets and calipers, as you will be purchasing new 87+ rotors anyway. It will all bolt right on, the only other issue being the dust shields. The 85-86 dust shields are too small for the 87+ brakes, thus the 87+ shields must be used. However for the dust shields to be replaced, they either must be cut, or the hub must come off. Since this may be more than some want to have to do, you don't have to reinstall the dust shields. Is it worth installing the dust shields? This is a topic that has been discussed in length on the Mr2 list with some good conclusions made. The original purpose of the dust shields is to keep rocks, dirt, etc. from getting into the pads which was once a much larger problem than it is today with newer technology pads. By taking off the shields you allow a greater amount of cooling air to contact the rotors, thus greatly increasing the rotor life and repeated stopping ability, as the shields act like a heat radiator hindering rotor cooling. So why would you keep them on? Well, if the car is going to be used on the street the original purpose of keeping dirt out still holds some value, but the one major reason is water. If you drive the car on the street often and get the brakes relatively hot and then splash in a big puddle, the shields greatly reduce the amount of cold water from contacting the hot rotors, a recipe that normally will warp rotors. So what do you do? If you drive the car in mostly good weather or are very conscious about how much water you are splashing around in, taking off the shields may be for you. On the other hand, if you won't be calling upon your brakes to do repeated hard stops, and like the security they give you, leave them on. As you can see under the brake upgrades below, a good set of pads and performance fluid will go a long way to cure fade problems.
Caliper Rebuild Here is my post to the MR2 list after rebuilding 2 sets of AW11 brake calipers:
Frozen Parking Brake A common problem for MKI owners during the winter is that the parking brake will freeze in it's locked position overnight. This is usually due to water that has frozen in the cable. You can either leave the car in gear the night beforehand if it is not on a steep grade, and/or place a stone in front of the tire. You can also *gasp* drive it until the heat from the engine unfreezes it, that is if your brakes don't catch on fire first... Then on the other hand, some owners will come out on a nice warm sunny day to find the same thing happening! In this case the cables have just simply become stuck and will not release the rear calipers as dirt and rust will find its way into the cable. Most often the moisture and/or dirt gets into the cable because the thin rubber covers at the end of the cable easily get ripped up due to age. In either case, it is usually always futile to try and repair the old cables. Thus it is necessary to purchase new ones from Toyota. Also this is sometimes due to sticking rear brake calipers that need to be replaced/rebuilt. Also don't forget that the parking brake cable will often have to be adjusted afterwards. This can be done by accessing the point underneath the car where the two cables meet together to form the "V."
Brake Upgrades
Hardware Upgrades As you may have already read, the 87+ brakes are different from the 85-86 brakes in that they have a larger rotor with larger corresponding mounting bracket. If you are having rotor warpage problems, this is an easy and cheap upgrade. If you are looking for something better than this, there are now some options that were not available before. There is at least 2 big brake upgrade kits out there now, and I wouldn't doubt there are more. Check out the Mr2 list archives, especially the mr2sc list archives if you are interested. Here is the KVR upgrade used by both Tommy G., and Dave K.
This mod will require 15" wheels if you do not already have them. Please contact KVR at 1-800-636-0854 or go to their website for further info.
Pads Luckily there are many different performance pads available for the AW11. The most commonly used are Performance Friction, Hawk (Mostly used for track only), and Carbotech. Here is a listing along with specs for different pads that was reported on the MR2 list. While I know this table is getting old now, it will be left up for reference.
Notes about pads: The amount of track days can vary widely and it often depends on the driver and type of course. This statistic was just put along to get an idea of how well the pad holds up to the rigors of track racing. Many have had good results in using performance pads on the rear that have a higher coefficient than the front to help balance the load some, as the rears will never lock up with the stock pads. One must be extremely careful however when using different coefficients from front to back, as to not throw the balance off too much, as a system where the rears lock up first will promote a spin. All those with aftermarket pads have reported better modulation, but seeing as this is a very subjective measurement, I can't really comment on which is better than another. One other thing to consider is that Ferodo is terminating all of their old pads and this rating really doesn't mean much anymore. Some pads are made for just for the rears and vice versa, and you can also have custom ones made with the compound of your choice. Many have also found that even after using high-performance pads, that the stock pads themselves are not really that bad. For instance a setup used by many is the stock front pads, with a set of the Mean Greens or Axxis on the rear.
Rotors As already mentioned above, sooner or later, as an Mr2 owner you will have to deal with the annoying warped/worn out rotor problem. This can come from over torqued wheels, putting on the parking brake after getting the brakes very hot, or just simply flogging the brakes time after time. So what are your alternatives now? The stock rotors are not too bad, and are moderately priced. Brembo offers 2 types for the AW11 the first being a high quality OEM spec rotor for about the same price as the Toyota ones. They also make a cross drilled rotor for about double the price. Powerstop offers a high quality cross drilled as well, and power slot offers a slotted rotor. I'm sure that there are also other OEM sized rotors out there from other companies. So which one do you choose? Well if you are looking to sacrifice longevity for more raw braking power by all means go with the slotted or drilled. These will offer greater braking power, but will wear out pads faster, along with the fact the rotor itself usually wears out more quickly than the stock rotor. If you are looking for a high quality rotor which will still give you good power but last longer go for the Brembo OEM spec or Toyota. These will last ok, and will not give you problems on the track. If you are having fade problems, it is usually never the rotor but rather the fluid, pads or lines.
SS lines SS lines are available from Goodridge and TRD along with various other manufactures. The TRD lines however are just Goodridge lines sold by TRD as a TRD product. Who knows if the lines offered by the various other companies are made in house, or once again are repackaged Goodridge lines. Once pad and fluid issues have been addressed, the stock lines have reported to be a possible Achilles heel of the car at track events, however this it not true for all. Either way, if you go to track events and think that you are having problems with the rubber stock lines ballooning, go with a set, they don't cost that much. (~$110) This is often the last item to be upgraded however, as it is the least important after fresh fluid, pads, and rotors are installed.
Fluid Performance fluid is a must if you are having fade problems. There are many different HP fluids available and all work pretty good. Some of the more common are: Motul 600
Both the Motul and AP are pricey but nevertheless are high quality brake fluids. However, whenever doing brakes, the author will head up the Ford dealership for a couple of fresh cans of HD fluid. Its cheap, can easily be found all over the nation, and it performs quite well. This is a common choice for many MR2 owners. New alternatives also come on the market all the time, so don't take this as the only options around.
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