Mazdaspeed3 Brake Conversion on Mazda 5 ?

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Silentnoise713

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2008 Mazda5 GT
Anyone tried a MS3 brake transplant onto a M5? I would image the braking system/components between the M5 and M3 are the same, if that is the case, an MS3 upgrade to the M5 would be awesome cost effective upgrade. Also, this would mean BBKs for MS3/M3 would also fit M5.

Google hit for MS3 to M3 conversion.
www. mazda3 forums.com/index.php?topic=143970.0
 
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I heard somewhere that the 5 and the speed3 have the same calipers, the 3s rotors are a bit larger, so you'd have to get the proper parts to change up the rotors, but might as well go with aftermarket ones and nicer pads...
 
Really!? That would be a pleasant surprise but I am skeptical until I see confirmation. Based on the size of the rotors, it looks like the 5 has the same front brakes/calipers as the 3 (11.8", makes sense for component sharing and cost) and rear brakes/calipers as the CX7 (11.9" bigger than the front for the potential added weight in the back).

A MS3 has 12.6" rotors, which are pretty substantial for OEM (370Z has 12.6” front), and stops about ~12’ feet less than a 5 from some of the online numbers (apples to oranges comparison: more weight and master cylinders *might* be different but can prob swap that too). Assuming if the calipers are indeed the same you would only need a MS3 caliper bracket (~$40 each) to fit 12.6” rotors onto the 5. Everyone should be jumping at this to improve braking along with a nicer set of pads. The only other thing you need to make this a mini bBK is SS brake lines, which I image are available and cheap for the 3 and interchangeable on the 5. It’s not +13” rotors (some require 18” rims to clear) or multi piston calipers but think how much are you getting for such a small investment.

BBKs are nice to look at but not worth the price unless you are going all out all the time or don't know how to use your money better (you wouldn't be driving a 5 ). We are talking $2-$3K vs. a few hundred bucks for substantial improvement.

I’m surprise no one has done it or try to do it.
 
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Silentnoise713 said:
Really!? That would be a pleasant surprise but I am sceptical until I see confirmation. Based on the size of the rotors, it looks like the 5 has the same front brakes/calipers as the 3 (11.8", makes sense for component sharing and cost) and rear brakes/calipers as the CX7 (11.9" bigger than the front for the potential added weight in the back).

A MS3 has 12.6" rotors, which are pretty substantial for OEM (370Z has 12.6 front), and stops about ~12 feet less than a 5 from some of the online numbers (apples to oranges comparison: more weight and master cylinders *might* be different but can prob swap that too). Assuming if the callipers are indeed the same you would only need a MS3 caliper bracket (~$40 each) to fit 12.6 rotors onto the 5. Everyone should be jumping at this to improve braking along with a nicer set of pads. The only other thing you need to make this a mini bBK is SS brake lines, which I image are available and cheap for the 3 and interchangeable on the 5. Its not +13 rotors (some require 18 rims to clear) or multi piston callipers but think how much are you getting for such a small investment.

BBKs are nice to look at but not worth the price unless you are going all out all the time or don't know how to use your money better (you wounldn't be driving a 5 :D). We are talking $2-3K vs a few hundred bucks for substantial improvement.

Im surprise no one has done it or try to do it.
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i've looked at it, but haven't done it yet. try to find a set of mazdaspeed3 front caliper brackets, then post back. i bet you wont be able to find any outside of mazdaUSA.

for the 5, just get some hawk hps pads all around, maybe some SS brake lines, and call it a day.
 
No doubt a nice set of pads is the easiest and MOST cost effective way to go, but there is a lot of potential with this upgrade. We’re not talking about 2-3’ but potentially over 10’! That is a lot. Come to think, didn't the folks who built the MazdaSpeed 5 also transplant the MS3 brakes? Braking is just as important when going fast and for control.

There is "1" bracket on eBay but you still need the find the missing pair :D. For the ultimate cheap upgrade you’d have to hunt junk yards, craigslist, and MS3 forums for it. Nonetheless, even if purchasing from MazdaUSA the brackets should not cost much – it’s a metal bracket.

This is what 1.6L Miata community did to get the larger 1.8L brake upgrade -getting the larger bracket from the 1.8 and everything is bolt-on. Granted smashed up Miata’s are a dime a dozen. The bracket allows you to clear a slightly larger rotor and larger pad (calipers were the same but mounted upside down-if I remember correctly. Brackets were $80 new each –don’t recall exactly). The rotor size difference was not as drastic between the 5 and MS3.
 
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I know this is an old thread, but I found it interesting and started snooping around for answers. Parts have become available so this is easier to confirm, but the front calipers are not identical. Via RockAuto the MS3 calipers are only for the MS3 and two Volvos (all similar chassis of course): the S40 and V50 in T5 trim (the upper trims). The MZ5's are shared through the 3s and GT ranges along with all 5 trims. The piston body could well be the same since the bores are identical (57mm) though the overall body (and bleeder screw) is different. We have both cars (see sig) and visually you can see the pad "seating" is different, thus the pads are different.

I would be interested in a more technical breakdown and would not be surprised if the main improvement between the units was pad bracketry allowing for a larger pad to grip a larger diameter rotor. In which case actual piston pressure may the same or very close..?
 
Next time you do a brake job, you can try and swap a caliper from the M5 over. To make it easier, try to source a junk caliper from a M3 or M5 to test fit on the MS3 bracket. This way you do not have to open/expose your brake line on any car just for a test fit.

Can you also visually confirm if the master cylinders are the same? I am fairly confidant these parts will fit and just b/c manufacturer list two parts numbers, does not mean they do not fit.
 
If the Mz5 is using the same calipers (currently) as the 3s then swapping in the MS3 calipers shouldn't be an issue at all. Actually a lot of Mz3 guys with the 2.0 3i are doing the swap to MS3 fronts and Mz5 rears.
 
I don't believe the cross references at rockauto are complete as the brake calipers all show interchange between the (2008) Mz3, Mz5, Ms3 and Volvo S40 V50 if you browse to each vehicle. It appears they all fit each other.
 
From what the Mz3 guys are saying you only need the MS3 caliper (with bracket) the upright/transverse bolts, rotors and pads in order to do this mod. IIRC the bolts cost about $20-30 from the dealer and they're definitely two different sizes.
 
icspots said:
From what the Mz3 guys are saying you only need the MS3 caliper (with bracket) the upright/transverse bolts, rotors and pads in order to do this mod. IIRC the bolts cost about $20-30 from the dealer and they're definitely two different sizes.
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What I am suspecting is that all you need is the MS3 caliper bracket -PERIOD (perhaps the bolts if length/diameter/pitch is different). You can then source your own favorite brand of aftermarket rotors and pads to make an awesome upgrade for very little money, essentially the cost of a pair of MS3 brackets (+bolts).

Quick search found this.
http://mazda3 revolution.com/forums/2010-mazda-3-wheels-tires/5395-2010-mz3-2-5l-ms3-front-brake-conversion-3.html
The Mazdaspeed and Mazda3s (according to centric brakes) have larger caliper piston bores 57mm vs 38mm which helps to distribute the clamping force better and/or increase it. Other than that the calipers are identical with different mounting brackets.
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Not sure if the Mz5 piston are 57 or 38 but it should be usable nonetheless. Of course the bigger piston would be more effective.
 
^^ I'm pretty sure the bracket is a part of the caliper.... not positive on that though. And yes the piston size is larger on the MS3 brakes vs. both the Mz5 and Mz3.
 
I'll have to actually pop a wheel, but it appears the MZ5 and the MS3 piston bores are identical from the specs I've found and general knowledge across boards. It's the bracketry surrounding the pad that is larger on the MS3 - that much is not the same and is easily seen. I wanted to see if an MS3 would look dumb with a 17" rim and was going to put one of the MZ5 rims on just for comparisons sake so I'll have both brakes exposed and can poke around.

I realize RockAuto is NOT a positive confirmation of pretty much anything ;) Just one particular point of reference. However, it would make sense to have different pad specs on a larger rotor to better match the larger arc length even if the piston mechanics were identical. Not strictly necessary, but an easy way to get more surface.

I thought I was subscribed on this thread (sorry I'm getting used to being on a BB again) so I didn't follow up. I'll come back more quickly this time!
 
Hey Jack, Did you get a chance to confirm if the master cylinders are the same? I found an old thread which states that it 'may' be different and since you have both cars, it takes but a few secs to pop the hood for a visual confirmation. Thanks.

I'm more inclined to believe that the MC are the same but caliper piston bores are different. I don’t think Mazda will engineer a unique MC just for the MS3, unless it is also shared with another car –RX8 or Miata perhaps. Also, it's not like BBKs come with dedicated MC.

http://www.mazdas247.com/forum/showthread.php?123759412-MS3-Brakes-on-M5-Has-anyone-done-it
 
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Speed3 Brakes are an upgrade on the 5 for the fronts, just as the 5 rear calipers are an upgrade on the Speed3's...

Check out CAIN on mazda3 forums.com for more info...
 
ScratchNSniff said:
Speed3 Brakes are an upgrade on the 5 for the fronts, just as the 5 rear calipers are an upgrade on the Speed3's...

Check out CAIN on mazda3 forums.com for more info...
Click to expand...

do you have a link for that thread? thanks.

i need to get the brakes done on the wife's 5, and i am SERIOUSLY considering the speed3 fronts. i'm not looking forawrd to breaking the line from the caliper, though...
 
It won't transfer the link to over there since it is blocked, but look on mazda 3 forums and it is his build thread for his 3...all of it is discussed in full there...he can answer any questions you may have...
 
Finally...

Sorry it took so long, guys. Don't have a good excuse, just busy... Here are the results:

While I didn't take the rotors and pads out I did measure the outer diameters of the caliper pistons. The MS3 caliper has (as you will see in the pics) a lot more metal overall, this includes the metal surrounding the piston bore. The OD of the MZ5 was about 2 3/4" and the MS3 a hair under 3", but the amount of metal around the piston was greater, which puts the piston bores close to, if not exactly identical. This gels with parts lookups.

MZ5 shot 1 MZ5_Cal1.png
MZ5 shot 2 MZ5_Cal2.png
MS3 shot 1 MS3_Cal1.png
MS3 shot 2 MS3_Cal2.png

But despite any similarities with the pistons, because the mounting is integral I don't see how you could reuse it on a larger MS3 rotor. And even if you could, you'd be stuck with the smaller MZ5 pads.

On to the master cylinders...
 
Finally, part II...

The master cylinders, like the pistons, appear to have similar hydraulic dimensions (although it's much harder to get at both of them for a good comparison). But the reservoirs are VERY different and that aside the bungs are very different as well. I'm not saying you definitely can't exchange them, but it would take some finagling.

Anyone with a 5 might notice the "dual" tank reservoir. There's one immediately on the MC and then there's a hose and a "remote" tank which is the one you fill. This appears to be purely pragmatic as you'd have no way to fill the main tank. It's just too far under the hood. The 3 has less recess in this area so it is a single tank design. It might be possible to swap tanks, though.

The bungs are pretty easy to see in the pics. The 5s are straight out:
MZ5_MC1.png
MZ5_MC2.png

The MS3s are angled down:
MS3_MC1.png

In this case is the MS3 that has the clearance issue. As such I believe it wouldn't be too much of an issue to put that MS3 MC into a 5, you'd just need to bend the tubes a bit. I think to go the other way might be more difficult, having less clearance. Again, bores seem similar if not identical, but perhaps there is more to them that makes them different. Certainly the MS3 brakes feel much harder, less spongy and more responsive (not that the 5 doesn't have really good brakes).
 
Finally, in summation...

The summary points here are that the Speed calipers are different. Maybe the end result is that they are simply reinforced and can handle a larger pad (i.e. pistons are equal) but they are definitely NOT the same. The MCs are also similar in rough external dimensions but not equivalent.

I wouldn't hesitate to put the MS3 front hydraulics on while retaining the MZ5 MC. However, if it didn't feel right figuring out how to get the MS3 MC in there would be my next step.
 
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