A bolt-on solution using the flat brackets

[Guest Anonymous]

I found a rotor that will work with 87-89 rear Z31 calipers and the flat maxima brackets. That's a single piston, sliding caliper with cable parking brake and a 0.81 thick vented rotor.

The rotor I found is 11.1 diameter and the friction surface is 1.9 wide - the z31 brakes use a ~1.5 wide friction surface. So there's plenty of room to turn the rotors down slightly if the maxima bracket puts the caliper too close to the wheel axis. The rotors also have 5x4.5 bolt pattern as well(I think, only had a ruler to measure, might be 5x4.75, but I don't think so).

The rotor offset is just a hair too much, but it oughtta all work together just fine. Worst case scenario is you'll need to duplicate the flat maxima bracket from slightly thinner metal, not a big deal. The parts store couldn't tell me an application for the rotor from the part # on the box though. Morons. Can anyone look that up for me? I have IPI, raybestos, mpi, and foster part #s for the rotor.

So, the rotor will need to be drilled for 4 bolt people, probably not if you're using 5 lug. And it might need to be turned down by 1/4 inch or so, dunno about that yet. 87-89 rear calipers are the same on turbos and non, so they are readily available. The parking brake cable goes forward though, not towards the center of the car like the s30 e-brake cable.

And it all bolts right on with OE parts! (99.9% sure it does anyhow!)

 

 

 

 

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Morgan

http://z31.com/~morgan/s30

http://carfiche.com

[Mikelly]

Morgan, What is the part number... I'm going 5 lug in the rear, and if I can sell the rear disc setup I have, then I'll investigate this more and find the application.

 

Mike

 

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http://hometown.aol.com/dat74z/myhomepage/auto.html

"I will not be a spectator in the sport of life!"

mjk

[Guest Anonymous]

I didn't bring my scribbly piece of paper with me to work, it's at home. But you can buy them by the part # at any autozone/advance auto type store. I didn't inquire as to price, but I'm pretty sure it's for an american car, so it's probably a reasonably priced rotor.

New calculations: If the flange-hub distance is 2.125 like danno says(I guesstimated 2, but hopefully he's more accurate since his car is disassembled!), and the bracket is 10mm(not 1/2 inch) thick, then this rotor is off by 0.26 inches. The sliding caliper pins could probably account for 1/4 inch don't you think? A new bracket made from thinner metal, say, 0.25 instead of 0.4, would get you 0.15 inches, leaving the alignment off by only 0.1 inches which would easily be absorbed by the caliper pins.

I think it will work with all the stock parts. If not, someone can make a few bucks selling new brackets(If that's the case, the brackets could be sized appropriately to make the rotor not require cutting too!)

 

 

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Morgan

http://z31.com/~morgan/s30

http://carfiche.com

[Guest scca]

i have the raybestos full catalog on cd rom.

so i should be able to x-ref anything.

 

helps when i sell phones to the raybestos rep

 

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Mike

mike@fonebooth.com

http://www.fonebooth.com/brakes.html

raceparts and brake upgrades.

[Guest Anonymous]

Well, I don't have it with me, but the application isn't a problem, you can buy them by part # all day long. The problem is knowing if it will fit directly on and properly.

I'm quite confident it will fit, the pins should absorb 1/4 inch. If not, a thinner flat bracket will leave the pins with only 1/10 of an inch to compensate for, which I know they will do easily.

So the diameter is the only real problem - and turning a rotor down a bit isn't a problem at all!

I'll post the part #s when I get home tonight. but if you can look them up, one of the part #s was 4414. I don't remember which brand that part # was for though.

 

 

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Morgan

http://z31.com/~morgan/s30

http://carfiche.com

[Danno74Z]

A = Diameter

B = Original Height

C = Original Thickness

D = Min. Thickness, i.e. Replacement

E = Center Hole

F = No. of Bolt Holes

 

I did a little research on the rear rotors for the ZX cars and below are the dimensions (all converted to inches). I thought this my help in the search for rotors. Number 2 below is a definite possibility using the bolt on Maxima bracket or the bolt on flat bracket. For folks that want to use a flat bracket just accommodate the increased rotor diameter by making your bracket a little longer. People using the Maxima offset bracket and depending on which caliper they use have a little more work but not insurmountable.

 

The only real downside is #2 is a solid rotor not vented. But is this bad? Totally up to the end user.

 

1) 280ZX 81-84 (Z31) solid rotor

A=10.1 B=1.85 C=.39 E=2.67 F=4

 

2) 300ZX 85-89 (Z31) solid rotor

A=11.41 B=1.85 C=.39 E=2.67 F=5

 

3) 300ZX 89-94 (Z32) vented rotor

A=11.69 B=2.51 C=.71 E=2.67 F=5

 

I'm trying to insert a picture I have so this is a test.

 

Well the picture did not show up - HELP

 

I just figured out one needs a web page to insert a picture and link to it.

A = overall diameter of rotor

B = overall height from outside edge to outside edge (including hat)

C = thickness of wear surface

D = omit

E = Pilot opening

F = number of lugs

 

 

Danno74Z

 

 

[This message has been edited by Danno74Z (edited January 25, 2001).]

 

[This message has been edited by Danno74Z (edited January 25, 2001).]

[Guest Anonymous]

84-86 rear are a solid rotor. 87-89 rear are vented, 0.81 thick and 11.1 diameter.

The rotor part #s are:

76646 for raybestos

yh145152 for foster

1414 for ipi(not 4414 like I said earlier)

 

I am confident this will work with nothing more than drilling the rotor for 4 lug(the rotor is in fact 5x4.5, tested it on the 88) and maybe turning the diameter down a bit.

 

I am going to get a caliper and stuff from a junkyard and bring a bracket and rotor and pads and test it on a junkyard car ASAP. I bought the 1 rotor advance auto had - $40. not bad for such a serious rotor!

 

If you guys can look, what is needed is this:

0.81 thick(prefferably vented)

11.1 diameter(maybe smaller, but turning the OD down is not hard)

And most importantly: the offset from the center of the rotor(center of the friction part) to the plane that sits against the hub needs to be 0.5 ideally - the one I found is 0.75, but I think it'll be fine.

 

 

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Morgan

http://z31.com/~morgan/s30

http://carfiche.com

[Guest Anonymous]

For whatever it's worth...... I have a slight concern about the calipers hitting the wheel with these brakes.

The face of the rotor is about 0.75 inches(maybe a bit less) back from the plane where the wheel mounts. I figure my panasport wheels give about 0.5-1 inch of clearance to the mounting plane. Total clearance: 1.25-1.75 inches.

Figure the brake pad is 0.75 inches thick, that leaves as little as 0.5 inches for the claw of the caliper that reaches over to the outboard pad.

I think it will fit with my panasports, but I'm sure some wheels will have a problem with it. I'll try and get some measurements this weekend now that I have one of the rotors to play with.

 

 

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Morgan

http://z31.com/~morgan/s30

http://carfiche.com

[Trevor]

Another possibility for rear vented rear disc rotors are from the '81-82 Toyota Cressida. I don't know the diameter. These have a pretty deep hat because they drum-type parking brake is inside the hat. They have 4 x 4.5" lug bolt circle.

[pparaska]

This sounds much like the conversion I once had on my car, but never used. It uses a flat bracket, early (79-81) ZX calipers, and late (82-83) discs. It has wheel/caliper interference problems with some wheels, but I took care of that (as shown on that page) by removing some material from the caliper yoke, which is huge. FWIW, here's the link:

 

Hybrid Early/Late 280ZX Rear Disc Brake Swap for 240-280Z

[Guest Anonymous]

Therein lies the problem - to use flat brackets you need a very shallow hat-rotor offset.

 

 

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Morgan

http://z31.com/~morgan/s30

http://carfiche.com