You guys by now have heard of the Z31 Z bigger rotor upgrade. If not check Matt's site. A long time ago, he took his time/effort to research a BBK for the rear 3-gen maxima brakes. He had already upgraded is fronts to Willwoods eons ago. What this kit does is increase the amount of brake torque/work the rears do to compensate for the increased work that the front BBK does (if you have them so installed). But you have to source a pre-10/90 rear disc'd maxima brake brackets and drill new holes to accomodate the larger rotor. The rotor you use is from a Z31 300z. It's a bit larger. Mike93ve has been kind enough to research the best year Z to get the rotor from 1996 I believe 1986' is the year. Mike is also going to be kind enough to send me some brackets. I will have these put into a drawing and have some fabbed up. They will have the holes to use either the stock or the larger Z rotor. (If you every decide to swap). You get to use your stock calipers(I believe you have to use post 10/90' year calipers)

Now, I the problem is I have to meet a min. It will probably be anywhere from 4-6 sets. My BBK cobra rotor brackets were about $45 shipped. I will assume I can sell them for about the same. But I won't know until later. This bracket is flat but more complicated.

Now for the BBK guys, this is a no brainer. But you have to dig around some boneyards until you can find some. They are only $15-$20 but what a pain in time. You guys should consider this. But AFAIK, there is only about 2-3 3-gens that even have bbk or even plan to.

What would be an interesting project is to find out how well this works on a stock braked maxima. Now if you ever noticed, the rear brakes don't do squat! Even at 130k, my old maxima had it's original rear pads and they were like 90%! Sheesh! I believe Mike is going to try to do this on a stock maxima for research but it's gonna be down the road sometime.

So who would be interested? Only reply if you are realisticly interested. But hell, you would only be into it for maybe $45-$50-ish for the brackets and whatever stock Z31 rear rotors go for. If you didn't like it, you could swap back pretty fast.

 

I'm down Jeff (assuming price stays in that ball park).

I just want to make sure, will the larger rotors fit a stock wheel?

Also will they be predrilled with the 4 bolt holes? (just want to make sure).

 

Mike mentioned to me that it's REAL close. You might have to grind down part of the caliper to clear the 15s.

Uh the rotors will be from a 86' turbo or na Z31 300z. FIVE lug.

 

Sorry, will your brackets be predrilled with the 4 holes for where you mount the caliper (2 for stock rotor, 2 for the larger rotor).

 

i accually bought the z31 5 lug rotors back in october but have yet to find the right caliper bracket and think matt said to use the newer 91+ max calipers with the pre 91 brackets to get the right spacing to clear the rotors

 

I guess the biggest question about the rear discs being utilized is...how does the brake booster supply enough pressure to them...might need to upgrade the brake booster...with a Z32 unit perhaps.... there is plenty of room on the firewall...should be plug and play, not sure how much difference there is. The extra hydraulic pressure might be better than doing a BBK or help when you do one.

My 2 cents...

I'd like to do the kit, $45 you say? hmmm maybe get the other 6 and i'll have time to think.

Brian

PS. There is a set of Skyline rear calipers on Ebay...would those work for this setup?

 

Ah, you use the same caliper. No bigger MC needed

 

So its only changing the rotor size then?

so the actual brake pad area/clamping area isnt increasing?

So what is the benefit?

Brian

 

Increased torque due to fact that the caliper is away from the center of the rotor a greater distance. ie.. why AEM offers cheaper brake kits using the stock front honda calipers but with bigger rotors

 

So this kit should be ok using post 1990 hubs? Such as on the VEs...

Really besides ligtening the caliper weight, what is the benefit of the Wilwood or brembo packages over stock relocated kits?

The only thing can think of is that there is more surface area for friction or a tighter clamping force using a 4 piston/6piston over the stock 2 piston model...

Am I right in that understanding?

Brian

 

Jeff,
I would definately be interested. When would you have to secure the money?

 

Brian, do some reading on big brake kits. It should answer pretty much everything you need to know. Since this project doesn't directly involve bigger calipers, it's getting a bit OT

crsmax. Well I need to judge interest first. I might end up having to make 4-6 sets anyway. But I don't really want to have to sit on a bunch of brackets if I don't have to.

I "think" this might do some good things on even a stock maxima. But I'd hate to say 100% as it's not been done before and I'd REALLY want to becarefull about putting TOO much brake bias onto the rears.(on a stock maxima) But soley based on how much the rears DON'T get used, my theory is it might be okay.

 

i may be down depending on how bad the car stops with the 20's

 

I'll test monkey that for you

 

you know I am down...remember my email? so you know it.

 

Jeff...I'm in. Hopefully it's about the same price as the brackets you sold before or less.

 

Okay, since I got interest from some solid members, I'll try to get this going. Mike has to send me the brackets, I got to get a drawing done and get them fabbed.

 

Brian you sound like me 3 yrs ago when I was drilling this very same question on the 3rd gen board. I just couldn't see the benefit and thanks to the patience of those members and a little reading I finally saw the light. I was under the same impression, what's the benefit going with a larger rotor if the caliper/pads remain the same size.

Here's the deal to the best of my knowledge. In order for the Z31 rear rotors to fit you will need two major components to complete the set-up.
1) Caliper and torque member (that's what the FSM calls it, it's the u-shape bracket the caliper actually mounts to) from post 10/90 SE
2) The caliper mounting bracket (the bracket Jeff is refering to) from a pre 10/90 SE

Now take a second, run outside and look on the ID tag in the drivers door jam. What month/year was your Max produced. Depending on your production date you should be able to figure out which one out of the two major items you'll need to complete this set-up.

As Jeff mentioned I was able to source out the bracket that "I" needed (#2 from the list above) Also as Jeff mentioned, I'm willing to mail him one of my brackets in order for him to make a drawing a fab up a few sets. It goes without saying Jeff will post any related info when it comes to fabricating these brackets.

And to piggie back on something Jeff already stated, when you're ready to order your Z31 rear rotors tell the parts clerk you want a rotor for a 1986 Z31. Even though other years will fit the 86 model year seems to be the least headache when ordering. FYI I paid $17 each for my Z31 rear rotors.

Will this set-up fit under OEM 15" wheels. Yes it does fit but it has major rubbing on the inside of the wheel IMO shaving the calipers "should" eliminate this problem.

Jeff I'll try to get those brackets off to you in the next two days. Weds not looking good for me so I'll try for Thurs.

MIKE

 

Mike of Jeff, I'm a little confuse now.
I was under the impression that I could use my stock rear calipers, mount them Jeff's caliper mounting brackets, with Z31 (86 model) rotors. Is this correct?

Or is it require that you have a post 10/90 SE rear calipers? So my 93 SE rear calipers won't work?

 

jeff im interested

 

Pre-90 rear disc torque member(or caliper brackets)

POST-90 rear disc calipers. So you are fine Seamax.

 

Thanks Jeff. Now the search for some slotted or drilled Z31 rear rotors.

 

Jeff,
I know this has been discussed before as well, but I was wondering if the Z31 or even Z32 rear calipers could be used, especially now that it is possible to have a bracket made. If I remember correctly, the Z31 rear caliper is not that much different from the max rear caliper as the Z32 rear caliper appears to be.

See below from Matt some time ago...

it would be much easier to swap the Z31 parts. all you need are the rotors from a Z31. everything else is OEM.
the Z32 stuff is always possible, but I doubt you want to spend weeks of machining and several hundred bucks having custom brackets made. if so, then it's possible- go for it. otherwise, stick with the cheap (and just as effective) option like I did.



Quote:
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crsmax wrote on 10-15-2002 07:33 AM:

Damnit... When the parts are available... they can't be used... when the parts can be used... they're not available! Ughh... Ok. Thanks for the info. Even swiping the parking brake cable from the Z and re-routing will not work?

 

I don't know what advantage it would be to use a Z31 caliper? Is it a two piston? I really doubt it. Z32 is a 2 piston which would probably look nice and work well. But hell if I'm going to spend the $, time and effort to make it fit/work. Plus since 1 piston is on the outside, you have spoke clearance concerns again.

Why ice skate uphill? This is about as plug and play as it gets. Matt did the legwork, confirms it works great and has given me his "go ahead" to use his research for this.

If you would like to research this yourself, please feel free. I've already done the 300zx aluminum 4 piston/Cobra rotor upgrade. I've sent numerous brackets to people. I "think" one guy has actually done it (other than me) Turbo95.

 

Jeff,
Not sure if the Z31 is two piston or not. I am all for your set up. I was just wondering if the other calipers would be doable. I know you and Matt have researched this topic, and Matt and I discused like two years ago, but since you were going ahead with plans, I just threw out the idea. I am saving now for the front upgrade like yours.

 

the parking brake on the Z32 is the issue. it uses a drum-type parking brake where it's completely separate from the caliper. in order to make that work, you've got to fit all of that stuff behind the factory wheel bearing. tried it, won't work.

The Z31 rear caliper isn't any larger than the Maxima one, so hunting them down and swapping them will net you zero improvement, other than saying you got the parts off a Z. (woah. that'll improve your braking) making the parking brake work is another issue altogether.

of course, any goober can make a bracket to fit the calipers back there if you REALLY want the Z32 calipers (it'll take me an afternoon).. but it would be illegal to run them without a parking brake.. and it's a fine of $5000 for each offense of a person knowingly disabling the safety systems in a car (i.e. selling or installing a brake kit with no parking brake). No thanks.

 

Point taken Matt and Jeff... Thanks.

 

stupid question, how much bigger is the 300z rotor from stock?

 

bout an inch.. pics on my website.


my rusty stocker on top, Z31 on the bottom, and to the right.

 

great initiative on getting this rear setup going jeff and matt!

matt: you do have the z31 conversion on your rear right? how do you feel about it personally? worth the 125 - 150 bucks or so it will cost with rotors and brackets to get it done?

 

I've had it on mine for a couple years now. VERY much worth it, but only because my front brakes are so huge, I was having bias problems, and the rears were doing zilch.

 

Okay, Candiman has sent the brackets. So probably next week is the time I get to the fabricators for a discussion.

 

im looking for the rotors online. are we looking for the turbo or non-turbo 300z rotors and are they vented or non vented( i assumed nonturbo= non vented, but not sure.

here are the dimensions for the ones i found:

BREMBO 25138
ROTOR
Note: Rear; Solid Disc; to 8/1986; Overall Dia.: 290.0; Min Thick: 9.0; Height: 47.0
BREMBO 25466
ROTOR
Note: Rear; Vented Disc; From 9/1986; Overall Dia.: 282.0; Min Thick: 18.0; Height: 57.4

i assume #1, but u be the judge

 

With this being said I feel everyone wanting or debating Jeff's bracket should understand something.

Jeff's bracket will only work on a Max if the production date is after 10/90 So please take a look at your VIN tag in the divers door jam.

If your Max production date is before 10/90, Jeff's bracket will not work for your car. You will need other things in order for the Z31 rotors to work for you

This Brembo rotor does appear to be the correct rotor
BREMBO 25138 ROTOR Note: Rear; Solid Disc; to 8/1986; Overall Dia.: 290.0

IMO why buy Brembo's when you can walk into most parts store and buy a rotor for $17. It's your money and I honestly believe you get what you pay for, but for this case a local parts store will work for me.

Even though other years will work (NA or turbo) the 86 model year seems to be the least hassle when ordering. Taking a look at this pic you can probably see why. When buying a 86 rotor from a local parts store the only question they might ask you "Is it 4 or 5 lug"

 

actually i was ableto score those pretty cheap thats why i asked. thanks for the correct dimensions.

 

w00t! Sweet, I didn't realize that the rear rotors would be so cheap

Mike, what would be involved for a pre 10/90?

 

To the best of my knowledge (without trying to confuse you guys more) in order for the pre 10/90 Max to use the Z31 rear rotors you guys will need a few items from a post 10/90 Max. These items are:

1) Calipers
2) Caliper mounting brackets or torque member as the FSM calls it (this is were the confusion begins) This is not the same bracket as Jeff's bracket, it's the actual u-shape bracket where the the caliper mounts onto and where you put the pads.
3) And maybe the parking brake cables, I think ?

Some of you guys have probably already figured it out or knew what they needed but I would hate to see someone with a pr 10/90 Max buy Jeff's bracket and it doesn't work.

Let's use shavemax for example. From looking at his signature profile we see he has a 89 Max, without going any further it's obvious he can not use Jeff's bracket. Maybe he knew this maybe he didn't, just wanted to make sure.

This was the only reason I posted what I did three post down. Because I saw a 89 Max owner asking about Jeff's bracket. I can't stress it any further, the production date tells it all.

MIKE

 

thanks for the concern mike, but actually my car is a gxe,and i have struts off a 92 that i am customizing to put on the car, so no problem here. i now understand what is needed( i thought that it would have been the actual part of the strut where the calipers mount up( inthe front it's the knucle or spindle dependiong on how you know it.) that beng the case it should be faily simple for anyone who has a pre 90 maxima to do it( 90 and up se parts are more readily available than pre 90). ill post pic of the piece(caliper mounting bracket) you/re talking about so there isnt any more confusion.

 

thanks for the concern mike, but actually my car is a gxe,and i have struts off a 92 that i am customizing to put on the car, so no problem here. i now understand what is needed( i thought that it would have been the actual part of the strut where the calipers mount up( inthe front it's the knucle or spindle dependiong on how you know it.) that beng the case it should be faily simple for anyone who has a pre 90 maxima to do it( 90 and up se parts are more readily available than pre 90). ill post pic of the piece(caliper mounting bracket) you/re talking about so there isnt any more confusion.



caliper and torque member sepperate


caliper and torque member together



and for craps and giggles my new struts with 12" cylinders welded in them

 

Ok cool. Maybe I'm just making a bigger deal out of it. Looks good.

MIKE