GC71

I am thinking of getting the Project Mu 6 pot BBK and moving the original 4 pot Brembos to the back.

Just wondering if anybody has done this and what are the issues if any that were encountered if this mod is even possible?

The main issue I see would be 1. fabricating a bracket so that the front calipers can be fitted to the back, 2. Fitting on a propotioning valve to regulate the bias although I do know this i no tthe ideal way of doing it.

I am not worried abt the bracket but more on the effect it will have on the brake balance.

I know of someone who has Project Mu 6 pot BBK's that are meant for the front on both the front and rear of his car and they seem to be working fine.

o2sys

iTrader: (27)

I think the amount of work required is not worth it. Im curious to know as well, but could be just easier to do aftermarket rear bbk.

Hey if you can afford 6-pot project mus then y not there rear??? lol jk

you could sell the brembos and use the money for the rears no???

GC71

Not sure of the amount of work involved, but as I intend to keep the original brembos, might as well put them to good use..and a car with 6 pot up front and 2's at the rear seem kinda funny!..then again, having f/r calipers with colours that dun match are also uncool!

Am trying to curb my endless spending into the black hole especially during this stormy period, so just keeping it to the fronts..for now!

Chebosto

iTrader: (43)

so looking non-funny and cool is highest priority with your brakes...

*sigh*

if you really want to move your brembos (which are a different color than your pMu brakes, ROH-NOES!) look into getting custom brackets made- most machine shops can buy and cnc a bracket out of aluminum for caliper placement, however, something like this would cost probably in the several hundred dollar range (labor mostly, rather than materials)- and your brake bias would be in question, not to mention the rear hat of the rotors need to be swapped out to accomodate the Ebrake drum... (honestly our rears don't need anything bigger than a 13" two piston kit to brake well)

FYI brembo has a rear big brake kit application for our Z that they just released....

guitman32

iTrader: (15)

So, you're going to go through all the effort, fab a caliper mounting bracket, adapt a rear ebrake solution and some sort of proportioning valve...AND do the testing necessary to determine correct brake bias for your ride?

GC71

The main reason why I am considering going to a BBK is that my current set up with the brembos fade after 2 laps when I am at the track or drive aggressively for a short period of time and the rotors that were on the fronts have developed cracks so I have to look for a replacement or change my set up.

Don't get me wrong as I am a function over form guy when it comes to performance parts, just that it would be nice if the size/colours match up as well, and I think a BBK does add up to the look ofthe car.

I am not looking at throwing too much money into my Z anymore so just thought I'd use the fronts since I will be keeping them...saving up for a GTR

Your point on the E-brake drum is something I have not considered, thanks for that.

Was just wondering if this has been done before and what was the work involved to make this mod work.

Chebosto

iTrader: (43)

BBKs aren't Non-fade proof.. but i bet you had incorrect street pads in there for the track time, or were riding too hard on the brakes.

you developed a crack on aftermarket brembo bbk rotors? post picts please.

before you dump $4k on pmu bbk to solve what you're thinking is a 'fade' issue, i suggest buying $2xx track brake pads, motul 600 brake fluid, do a proper bed in procedure and then see what happens.

JETPILOT

iTrader: (51)

The brake bias would be incorrect unless you install a brake proportioning valve. There is nothing wrong with the OEM rear Brembo's. I have 565whp and a full weight car which I drive @ Sebring and never had any issues with the rear brakes with hawk DTC-60 pads.

idrive_MD

iTrader: (8)

first, problems with your OEM brembos fading...before a race event you should make sure you have proper fluid in there, certainly not regular OEM fluid, you want race fluid, second the fluid shouldnt be too old, if you track your car a few times a year you probably want to put new fluid in it right before your first track event, yearly.

next are pads, you were probably overworking whatever pads you use. I suggest getting a set of simple yet affective Hawk HP+ pads and use them only on track days, it seriously only takes 45-mins to switch out all four calipers worth of pads. if those dont work well enough go one step up from them.

as for your rotors, OEM rotors shouldnt crack, drilled rotors can crack and cheap rotors can crack. again I suggest getting a spare set or invest into a highqaulity rotor company for long lasting rotor life. Get slotted or plain face, never drilled.

Hopefully you have braided stainless lines, if you dont then get them! Depending on your miles maybe go ahead and rebuild your calipers just to be on the safe side.

if none of that fully cures the problem, duct cool air to the brake system somehow.

now if that doesnt work than you either need to learn a new braking technique or upgrade to 2pc rotors or a larger BBK to help with braking force and heat dissipation.

Now with regards to the OEM 4-pot brembos in the rear, dont bother! The pistons are too large and the caliper is too big. if you insist on getting the Pro-M front BBK with out a rear (it cost a lot so i understand), but still insist on a 4piston caliper in the rear then I suggest you go through the hassel of correcly fitting Porsche Boxster/Caymen rear calipers. The porsche rear calipers may have 4 pistons but due to them being made for the rears they are much smaller in comparison to the 350Z front caliper pistons and probably come pretty close to the area %'tage of the 350Z brembo rear piston sizes. They are also similar in design to most aftermarket rear-BBK as most companies mimick the porsche brembo style.

The Porsche rear calipers essentially come in two different sizes, (i.e. Boxster and Boxster-S are different rear calipers, Boxster=Caymen) the Boxster-S are slightly larger and accomodate a larger/thicker rotor than the regular boxster. ideally, you'll want to seek out the boxster-S rear calipers as they are only slightly wider than the OEM 350Z rear disk (see below).

for reference:
350Z brembo rear rotor measure 322x22
boxster-s rear 4-piston rotors are 299x24
boxster rear 4-pot rotors are 292x20

in all honesty, you could simply just use the 350Z OEM brembo sized rear disk and fab up brackets to make the porsche brembo caliper fit the Z, the 1mm difference on each side of the rotor will not hurt you at all and this option will not require you to come up with an alternative rear e-brake option. The caliper should also be able to deal with the increase in overall diameter as well.

also another option in addition to the rear porsche caliper, you can source a larger rear 2pc rotor from racing brake for the 350Z, it measures 332x24 and keeps the integral drum rear e-brake because its made for the Z. alternative, racingbrake also makes a 2pc stock rear rotor for the 350Z track so that could be an option to think about.

why do I know this, I looked into it before when I was building my 240SX.

If you insist on having a 4-piston rear caliper I think this is the best/cheapest way to do it, you just have to choose 1 of 3 rotor designs and fab up some new brackets, the OEM brake line bolt should work since its brembo to brembo. Boxster-S rear calipers can be found on ebay from $200-$1000, 911 Carrera brakes might be the same size as well, not sure though....good luck!

links for stuff:
racingbrake 2pc rear OEM rotor
racingbrake 2pc larger rear rotor
racingbrake 1pc rotors for 350Z

JETPILOT

iTrader: (51)

What problem are we trying to fix here? The OEM Brembo rears are adequate for anything he can throw at them.

idrive_MD

iTrader: (8)

Per the OP, he's having premature brake fade with OEM brake system and he insist on purchasing a project-mu front BBK because he thinks it will solve his problem and he thought it would be neat to put the OEM front calipers on the rear...so I offered him some sound alternatives ranging from an improved stock setup to a unique front and rear BBK system.

IMO, i think he needs better pads, Hi-Q rotors, lines and fluid and he'll be fine.

GC71

Thanks all especially idrive MD, really interesting information.

Just to give you all more background as to where I'm at..

I started first with a pad change early this year after I got booosted to the Endless super street something F/R, then upgraded to S/S lines at a later stage, then changed my rotors to some aftermarket slotted and dimpled ones..abt 4 months ago, I changed the front pads to Seido Ya N1 500 as the Endless Front pads were damanged by the installer during the rotor change. These pads are way much better then the endless might i add..the initial bite is really good!..anyway..

2 weeks before I went for my track session, the car had a complete fluid change and used Motul RBF 600. The brake fluids were changed and bleed with me watching over the whole process...I beleive I'm not the only **** car nut who does this cuz I know of a few other guys who are like that!

A couple of days later when i was driving the car hard for abt 20mins, I felt the pedal mushy and it had a sinking feeling..the similar feeling came back when i was at the track..that was when i realised that it was probably time for me to step up to a BBK. A couple of weeks after that, I realised that the front rotors were cracked. I travel so do not drive the car often..I must admit though that I am a late braker(which is the wrong way to drive this car) and hence a little heavy on the braking system, but all the pads, rotors etc were bedded in proper.

At the moment I am in communication with the people whom I bought the rotors from regarding the cracks so I am not at liberty to state the brand, but what I will say is that I have learnt a valuable lesson from this.

jakesford

Somethings not right... the stock bembos can handle quite a bit of abuse especially with the right pads and fluid. Forget the rear brake idea, there is plenty of braking force front and rear with the stock brembos, at the end of the day you are limited by grip. With MOST BBK you are limiting wheel choices, forcing the use of a larger diameter (probably heavier) wheel for clearance, and adding heavier brake components.

Check for fluid leaks on all the lines and on the calipers. Also check the MC and ABS pump just in case. If there aren't any leaks go back through all the steps of changing the fluid bleeding etc. Also I would take a look the pistons on the calipers and look for damage. Finally next time you go to the track take an IR thermostat and take some temp readings, if one side is hot you can focus you attention to that corner.

idrive_MD

iTrader: (8)

just to offer another opinion...project-mu is good and all, but in all honesty I would just save my money and get a more than adequate BBK system from wilwood, stoptech or racingbrake.

Project-mu endless and rotora are awesome setups but those I feel are more for those individuals looking to brand ***** but still need better brakes...or simply just want them for the baller look status.

i left out AP and Brembo as recommends because they cost considerably more than the first three.

it sounds like you went with some smart parts, I hope the rotor issue gets resolved and maybe start spending your track days or road excursions on braking technique since you admitted to being a late braker.

what kind of tires you running? poor grip tires will also require you to work your brakes harder, so if they're not exactly the stickiest you can bare, you may want to upgrade those too.

jakes IR test suggestion is a good one too, it will at least allow you to see where you are and how you've improved in either technique or with parts...or at least tell you how hot your pants get when you see a hotty.

guitman32

iTrader: (15)

It sounds like you could be boiling your fluid, especially if you're running r-comps combined with your TT power. From what I have read (ref: Jet's post below) if you just upgrade the fronts and leave the rear stock you should be ok