98SEBlackMax

iTrader: (9)

Ok this summer I swapped out to 300ZX 4 piston calipers and '04 rotors on my 4th gen. I like the extra heat capacity of this system vs. my old stock setup. I've yet to take the car to a road course with the upgraded brakes, but im sure I won't be chewing thru a set of front rotors every two track days like I used to.

Anyways the only downside to this mod is the slight bit of play and extra travel on the brake pedal. Id like to get the brake pedal and travel close to stock again.

From little I gathered the use of a 300ZX master cylinder would help fix this problem. Though I looked into the FSMs for the Maxima and the 300ZX. The Maxima system has a criss/cross setup and the 300ZX has a front/rear setup. Id figured id try it anyways. Worst case if it didn't work I would test it out and feedback my findings to the org.

Well from I gathered DON'T do this on a '96 Maxima or any 4th gen for that matter or any Maxima.

After swapping out the 300ZX master cylinder and making adjustments to get it all to work everything looked fine. I bleed the system and the pedal feel was very stiff with the engine off, I was putting a good amount of weight to see if the pedal would budge and it was firm. This tells me that the system is pretty tight hyrdaulicly. With the engine running the pedal feel was similar to what I had before. Now comes the fun part....

Took it for a test drive and it felt like I was driving with almost no brakes.

The only wheel that seemed to get enough pressure was the passenger side front. This rotor was the hottest of the 4. Like 1/2 hotter than the drivers side rotor...

Disconnected fuse 15 that powers the ABS module to see if it was some ABS error. The brake pedal had the same feel but when even lightly pressing the brakes the car pulls violently to the right and the right front tire locks up very quickly.

So unless I missed something the 300ZX MC won't work unless you re-plumb the Maxima brake line setup to emulate a 300ZX brake line setup. And even then theres no way to know if the Maxima ABS will work like that.

Don't think im going to put anymore effort into this. Im going to put back the stock MC and live with the pedal feel.

JonBlz

iTrader: (11)

you must have did something wrong a friend of mine had this in his car and it worked PERFECT he also did the Z32 f & r bbk setup and he did not have the same problem your having

MorpheusZero

iTrader: (10)

Wow... this doesn't make much sense. I have heard of people doing this mod before, worked fine IIRC.

Did you triple check everything?

Blackwind

iTrader: (9)

i was just thinking on this yesterday. in for the info.

98SEBlackMax

iTrader: (9)

FYI I used a new '90 300ZX master cylinder on a '96 Maxima with ABS.

Im thinking to try switching the two lines that are going to the 300ZX MC and re-bleeding the system.

I can imagine a change in brake pedal feel, but don't get how the hell this can be worse than before...

96blkonblkse

iTrader: (18)

Well, if the 300zx system uses a front rear setup, while the maxima uses criss cross, maybe thats why your only getting braking from the pass front wheel, and probably the drivers rear wheel.

I know people have done this and it has worked, perhaps try switching the lines and seeing if that helps.

Also isnt one of the main reasons to do the Z32 master, to get the brake bias more neutral again?

98SEBlackMax

iTrader: (9)

Another thing to add.

Has anyone who has done this swap tried pulling the 10 amp ABS module fuse? This shuts off the ABS brain and it goes to a default mode.

With my old OEM MC the pedal feel would be somewhat soft with the ABS functioning, with the fuse pulled the pedal felt alot more firm like my old non ABS '98. Id pull the fuse on some track days cause I found it easier to threshold brake with the ABS disabled.

Anyways with the ABS fuse pulled with the 300ZX MC the car is awful with the front right wheel locking pretty early. Im thinking the ABS compensates for the differences inherenant to the 300ZX MC and it is not as noticeable?

And yes im trying to get a more neutral brake bias along with a better pedal feel.

98SEBlackMax

iTrader: (9)

Ok the day after the initial install the brakes felt a little better. Then I set my static camber more back to around 0. I had the Stillen plates set to the most negative camber I could get. With the ABS fuse in and the camber close to 0 the brake pedal feel is liveable, but not much different than my old OEM MC. With the fuse out it still locks the right front wheel rather quickly.

Im still trying to work the bugs out of my Koni/GC setup then im going to get back to fixing this brake issue.

My thought is to re-plumb the brake lines so the front bias is correct and re-bleed the brakes.

Ghase

iTrader: (12)

It's sad to say the Z32 MC didn't do much for me as well on my maxima, but on my 240sx (S13) it was a far different story, work out great!!!.....

TJ_Max

iTrader: (10)

PM Vipervadim. He has this setup on his car and it works just fine.

98SEBlackMax

iTrader: (9)

I already got to see his setup.

His car is a '98~'99 with a different ABS brain than mine and he used a newer style 300ZX MC.

I have a new '90 300ZX MC and a '92 300ZX MC from a junkyard. From what I can tell the only difference is the electrical connector on the '91~'96 300ZX MCs are different than the '90 ones. Both say 1 1/16" for the MC size.

So the only big difference between his setup and my setup are the ABS brains.

Which is why I was suggesting people with this swap to pull the ABS fuse. Then find a safe area to test out the brakes and see if both front wheels lock first, which is the way it's supposed to be.

My theory is that the 300ZX MC is sending majority brake pressure to one front wheel and one of the back wheels. The 300ZX MC bias is a front/back setup whereas the Maxima MC bias is a criss/cross setup. With a functioning ABS the system compensates and it appears that it's working ok. Disable the ABS and it's a different story.

Once I get my suspension problems fixed I will look into this some more. Nothing is definitive at this time until my car gets a proper alignment.

Sinturion

Hey - any further on this? I'll probably be doing a brake upgrade soon after I do my turbo conversion.

98SEBlackMax

iTrader: (9)

Im looking to get a brake pressure gauge and test pressures at all four calipers. This way the suspension and tires won't play any factor in the braking results.

Though this won't be for a while. The fix should only involve re-routing one brake line by the ABS brain it should not be to difficult.

96blkonblkse

iTrader: (18)

I presume those Z's had ABS right? I noticed in the versa at my work(non abs), the front left wheel locks up first, all the time, no matter what conditions, or the speed. Tried it in my car, my front two lock up at the same time..i dont think the rears ever do or did lol. I have abs too.

If indeed the system is "confused" so to speak, with the Z's front/back while the maximas criss cross, you might try switching one of the lines. Youve already got it figured out what i was going to suggest, but try swapping one of the rear maxima lines to the front..vice versa to see if it helps.

I dont understand how some of these people have done the swaps with sucess but others havent.

Are you sure that there was no changes in the master cylinder in the Z's laterproduction run?

Just pulled this from Fast. Is yours a "nabco" one? Fast shows a differant P# for differant years, so it could be a change interally that you wouldnt notice by eye untill you actually took it apart.

Torgus

iTrader: (10)

i see something missing

Luquire

where is your brake booster hose

98SEBlackMax

iTrader: (9)

All Z32 300ZXs had ABS, turbo and non turbo models.

I was able to lock both fronts with the stock MC and the 10 amp ABS fuse pulled. Now for whatever reason it's not doing the same. As I said im looking at getting a pressure gauge and getting some actual data.

It could be alot of factors on my car but Id like someone else with the 300ZX MC swap to pull the fuse and test it out somewhere safe.

As far as I know the only changes from the '90 to the '91~'96 is the electrical connector. However there could be internal valve issues. I have a '92 MC that I will try if the '90 that is in my car doesn't work right.

98SEBlackMax

iTrader: (9)

It's not my car that's Vadims. Think he was doing some stuff to it when this pic was taken, cause yeah there are a few things missing in that bay.

KRRZ350

iTrader: (29)

First confirm with him that the 2 of you have the lines routed identical, if that's not it pop the cover off and play around with the brake bias, that's one of the nice parts about that set-up.

And I'll give a to everything working fine in his car, I've seen it in action slowing down from 130mph

96blkonblkse

iTrader: (18)

Copypasta from Wikipedia:

The Z32 chassis would likewise undergo several changes throughout its production run between 1989 and 1996. Among the milestone safety additions are the inclusion of standard driver and passenger-side airbags and true pillar-mount seat belts. The Z32's extended model year sales in 1990 reached 39,290 units.[11]

1991

Manual climate controls discontinued (except in convertible).
New electronic climate controls allowing control over air flow direction, but no more ambient temp gauge.
Nissan logo put on the front fascia (nose panel).
Driver's airbag now optional.
Air conditioner evaporator valve changed from aluminum to steel for better sound insulation.
North American brake rotors changed to NA units. Previous NA rotors were 4 mm thinner.
CD player option added for both the TT and NA; it was previously only available in the NA.
Bose stereo head unit changed.
Logo on floor mats changed from "300ZX" to "Z".
Hardtop coupe available at mid-year (NA only).
Brake master cylinder changed to new unit in February 1991.
Sales: 17,652 units.[11]

Check out this

http://www.importnut.net/300zxbrakeswap.htm#MC

What MC do you have? the 1 1/16th, 1" or 7/8th?

Sinturion

300zx:


95 Maxima:


I'm starting to think that removing the ABS would make things easier.

Sinturion

In theory - couldn't you gut the proportioning valve off the master cylinder and rely on the proportioning valve in the ABS to do the work?

Crusher103

iTrader: (10)

has a unit from a Q45 or J30 been tested? It might be able to deal with the 300zx brakes better than the stock MC, i dont think they would be too much different from a 4th gens MC, just a thought.

edit: nvm it looks like a simplified 300zx

98SEBlackMax

iTrader: (9)

Alright finally got a brake pressure test gauge and the results proved my theory.

Front Left PSI = 800 PSI with ABS on and off

Front Right PSI = 1400 PSI with ABS on and off

This explains the violent pull to the right under hard braking...

So the 300ZX MC bias is not right so I have to re-route the lines so that the front brakes are both 1300~1400 PSI.

I'm going to re-route the lines and bleed the whole system then measure the PSI on all 4 calipers.

98SEBlackMax

iTrader: (9)

Re-routed lines and bleeded the system like crazy.

1400 PSI on both front calipers!

Car stops very well now, no pull to either side under hard braking. Though there is a slight change in wheel direction on light braking, but the alignment isn't so good and im chalking it up to that.

panda_1

iTrader: (4)

has this been tried on a 5th gen with the brake swap yet?

98SEBlackMax

iTrader: (9)

It should work if the master cylinder bolts are in the same position. Then you have to bend the two lines going to master cylinder or get some new lines and bend them to match. Bleed the whole system and check for leaks. Then use a brake pressure gauge to make sure the pressure is ok on all four wheels.

yevrah4728

ok I've been looking, how would I get this to work on a non abs 4th gen?

back2basics

iTrader: (4)

reviving an old thread usually goes over like a fart in church, but I will second the motion for 4th gen non-ABS install.

I just ordered the rear big brake setup from Fastbrakes to balance out the front 12.6 Z32 fronts and I would like to install the master to boost the pressure in the whole system.

My biggest concern is making sure that my brake pedal is at approximately the same height under braking as it is currently so as to not screw up my heel and toe fun.

I am getting the final pieces together for the swap and really would like to do this at the same time.

Throw us a bone please.

mightyMax95

iTrader: (5)

i'd say install the MC, rerun all the lines, then have fun. just for kicks i'm going to run equal length tubing. if at all possible.

Crusher103

iTrader: (10)

get brake lines that fit, install and pray to the Gods when you come to a stop light.

It would most likely be easier to do this on a ABS car anyway, just cap the 2 ports you dont need and use the ones you do. The ABS will sort out the rest.

98SEBlackMax

iTrader: (9)

For whatever reason this 300ZX master cylinder setup never worked right on my car. I got amazing pedal feel and what felt like improved stopping power but it ended up leaking brake fluid.

When I got the lines re-routed the brake line pressure was ok at all 4 corners, but the 300ZX master cylinder always spat out a little bit of brake fluid every time I stepped on the brakes. On track days it PISSED out brake fluid enough that after a few laps I had to add more brake fluid.

I tried THREE different 300ZX master cylinders, a '90 and a '92 both were from junkyards and then I bought a rebuilt '91 master cylinder and all three leaked. I had some aluminum spacers made to go in between the 300ZX master cylinder and brake booster to see if that would help, still leaked and made the pedal feel worse. Gone through gallons of brake fluid trying every little thing I could think of. Finally I gave up and went back to the stock master cylinder and it does not leak even on track days under the hardest braking.

If you look on the 300ZX master cylinder there is a little valve that allows excess fluid to leave if the pressure gets to high. When I stepped on the brakes I could hear this little valve making a slight pop sound and spit out some brake fluid every time I used the brakes. I think it has something to do with the porportioning valve being built into the 300ZX master cylinder. The 4th gen with ABS has the rear proportioning valve located on the firewall and my theory is that this might be fighting with the proportioning valve built into 300ZX master cylinder. Not sure anymore as I cannot get easy access to that valve on the firewall.

If I remove the engine sometime in the future I might fiddle with that rear proportioning valve and use a vacuum pump to simulate engine vacuum to test the brakes. I have two brake pressure gauges that thread into the calipers if the bleeder screw is removed. I can check the front/rear and side to side bias to see if that will finally solve the problem.

For now I just deal with the brake pedal dropping a bit lower than it should and adjust my heel toe shifts as needed. It only sucks on track days when the brakes get really hot and the brake pedal drops a bit more. This throws off my heel toe and makes it difficult for smooth threshold braking.

Edit: Looking at the Maxima brake schematic I should be able to get a rear valve setup from a non ABS maxima and install that in place of the one with the built in proportioning valve. That combined with the rebuilt '91 300ZX master cylinder might just work...

yevrah4728

I was under the impression that they only had 3 ports for the lines (please dont flame me for this) maybe I've overlooked something but every pic I've looked at only has 3 (As you know, the non-abs 4th gen has 4 ports on the Master cylinder). I really need to do this swap since I've been running a 300zx brake setup for longest and the bias has almost put me in trouble a few times already. Please help!

back2basics

iTrader: (4)

If you look at this link http://importnut.net/300zxbrakeswap.htm#MC about half way down or so they describe that you have to remove a plug on one of the ports (don't remember which one but it's shown) and then install a new fitting for the line to attach to.

I'm thinking that with the use of the Z master and unplugging this port for access to all 4 lines to be used, it's just a matter of bending the lines to fit up and checking the pressure at each corner to make sure you are equal.

I would love ViperVadim to put in his two cents on how he did his and how well it has worked over the time it's been installed. I tried to PM him about it a long time ago and never got a response unfortunately.

TripleBLACKmax

i think beside unless you want to reroute lines you would have to stick with the stock mc. im gonna go out in the morning and take a gander.

back2basics

iTrader: (4)

Let us know if you come up with any new and/or relevant info. on this matter.

My rear upgrade just got here yesterday but they sent the wrong rotors, I wanted plain and they gave me crossdrilled/slotted, so now i have to get those replaced, fronts should be in hopefully in a week or two...just need more on this master.

asand1

iTrader: (1)

Front/rear MC generally have two different sized pistons. This will cause uneven pressures when plumbing crisscross.

back2basics

iTrader: (4)

I know I might be a little off on this idea but by looking at diagrams of the non-ABS cars the length of the front lines are reversed between the two models.
On the Z the longer line goes to the right side, on the Maxima it goes to the left side and reverse for the line going to the left front.

What I'm thinking is that I could just switch the right line to the left sides port and the left line to the right sides port, this should more closely balance the two but it would take checking the line pressure at each corner after doing it to actually confirm that assumption.

I'm not sure if switching those two would adversely affect how the brakes work, I don't really see how since all four would come on when the pedal is pressed (assuming the pressures at each corner are the same).

back2basics

iTrader: (4)

I sent Fastbrakes an e-mail asking about having to switch out the master, whether or not they felt it was necessary, and if they had an upgraded one already available.

Here is his response: The total piston surface area of the Z32 calipers is actually less than the maxima calipers(3.94” vs 4.04”) so you don’t need to change the master cylinder.

I mentioned that others on here had noted that the pedal does have a little more travel and that the general point of view was that is was due to the system now having eight total pistons instead of the original four.

He then added:
Yes that is really odd. The # of pistons only comes into play when adding the total surface area. The math doesn’t lie; the total area of the stock piston is 4.04 square inches and the piston area you measure for the Z32 calipers is 3.94. Based upon these numbers the pedal travel shouldn’t be affected at all.

Pedal travel will increase as the system gets overheated, but that is usually a function of the brake fluid boiling point. Caliper flexing when hot may also contribute to piston rocking in the bore, which would increase pedal travel.


So basically now I'm torn, should I bother? Is it worth the extra work and effort?

Crusher103

iTrader: (10)

See there is a reason we say what we say, the Z32 has 4 30mm pistons, thats 120mm in total, the maxima has 1 57mm piston. I dont know what math fastbrakes is doing but its over double the size on each corner.

A lot of people are using the lighter aluminium calipers aswell vs the stronger irons that are effected as easily by heat.