Which 300ZX rotor, front or rear for upgrade?

[ezzzzzzz]

Maybe I'm missing something but with the 280ZX caliper/300ZX rotor (front brake conversion on a 240Z), which vented rotor is used? Is it the front or rear rotor? Common sense tells me that the front is vented and the rear is probably solid which would answer my question. I don't have time to hit the JY's to research anytime soon. I want this upgrade and have credit at the local JY to pick up the pieces needed. They'll pull if I identify the correct parts. I just want to get the right parts first time. Thanks

[zcarnut]

Are you referring to this?

 

http://zhome.com/rnt/FordPower/BrakeUpdate.html

 

However, IMHO changing to a single piston sliding caliper and reducing the diameter of a rotor is not an “upgrade”.

 

I suggest you use the Search feature and research the numerous brake upgrades that have been already discussed here.

 

You are only limited by your wallet size

[A. G. Olphart]

I guess the meaning of "upgrade" must vary from person to person... I see a vented disc (only about 0.15" in diameter smaller per Terry's write up) as a huge improvement over a thin (much more easily overheated) solid disc.

 

Speaking as a wallet size limited individual, an effective junk yard solution can happen where new aftermarket parts will not. I think my discs came from an 85 (don't recall what other years are the same) non turbo 300ZX (Z31 model, 4 lug)

 

A cautionary note: When sourcing used discs a person needs to watch the thickness; they can be at minimum or below and still look pretty beefy.

Specs- Front vented 274 mm (10 3/4") .866 thick (.787 minimum).

 

 

With luck in the memory department I'll post some other measurements tonight.

[zcarnut]

For the same cost and effort a better solution is the 1986-88 Toyota 4x4 caliper (4 piston) with a 1985-89 Maxima rotor and a 280ZX hub.

 

No need to reduce the diameter of the Maxima rotor. You just have to get the rotor re-drilled to fit the ZX hub.

 

Junkyard parts are OK.

[A. G. Olphart]

Steve, does the setup you mention require the disc center hole to be carved out? I seem to recall a Maxima swap that did... personally, I'd rather work on the OD if that is the case. Also, are there any spacers involved? (Could be the swap I didn't find, but I'm committed now. The number of discrete variations of the Toyota 4 pot calipers also tended to frighten me while I was in the decision making phase).

 

I did check on sizes today... My cut down 300Z discs are only about a tenth of an inch smaller than stock Z's, which I see as insignificant.

Z pads are basically 2"x 2.9". ZX pads are about 4 1/2" long and 2" wide at their widest, but it (like the Z) is missing some corners, and the outer -long- side is an arc. Someone who retained more of their math skills than I, please feel free to compute the areas of both pad types. (By eye, the ZX pads are significantly larger).

 

Bigger pads, better cooling- works for me.

 

I don't have a bathroom scale at my shop, so guess I'll never know what the overall weight penalty is for my coil over/brake mods. Some things a guy just doesn't Want to know.

[datsunlover]

I plan on doing the toy 4x4 caliper/300zx rotor, and I can't see why people make such a big deal about the 'extra weight' it add's.. we're not talking 75+ pounds of stereo equipment which a LOT of people will toss into the trunk/hatch without hesitation.. (that extra weight also ends up ABOVE the center of gravity and adds NOTHING to the performance of the car..)

 

IMHO, a few extra pounds of mass hanging off the strut, is offset by the much improved braking ability of the set-up compared to stock. My stock 280z braking system has new pads, lines, been bled numerous times, it is in proper working order, and it works.. but FADE is a big problem (well, my driving style may be partialy to blame.. ) and frankely, I am a little frightened whenever I look at those sad tiny little solid disks..

[RedNeckZ]

I am using the 300ZX rotors (first year 300ZX model made with four lug pattern) on my 240Z right now. I have the S-12W (truck version) calibers from Toyota. I didn't have to turn down my rotors at all. It all bolted right up with the proper spacer. I don't think you will have to turn it down. Check it out first, bolt it all together and see if you will have to. I am also using the 280ZX rear rotor system. A lot of people do not like this system. But I haven't had any problems with it. Have had it on the car now for at least ten years now. Doesn't leak a drop. Got all of my parts from the junkyards in Greeley, CO. Also, have two extra sets of rotors and calibers from Z's I have taken apart. This system has been tested on the Second Creek Raceway in Denver a few times with the Z Club of Colorado. I used a flat plate (made by me) to mount my rear calibers up to the car. Other then that it was a easy brake exchange. I also went with the bigger MC out of a 280ZX (15/16") when I installed the brakes. It took a few rounds of bleeding to get all of the air out and had to adjust the pedal rod under the dash. But it gave me, the best brakes I have ever had with the Z. Look at all of the different ways people have done the brakes and do it your way. Good Luck and don't be afraid to ask any questions you may have, Rich.

[RedNeckZ]

Forgot to say, on the rear I have the early model 280ZX caliber and later model 280ZX rotor (small hat solid rotor). I also have just picked up the front and rear rotors from a 300ZXT and looking into how hard it would be to use both of them on the Z. Looking into what calibers I want to use and what kind of mounts I will have to make for the fronts and rears (both are five lug pattern). The price was right for me (free). Good Luck.

[blueovalz]

The primary reasons for the parts I chose for my first brake upgrade (using the 300ZX rotors and 280ZX floaters) were:

1) Lighter weight, which on a limited budget at the time looked to be the best alternative. Unsprung weight was something I wanted to avoid.

2) The 280ZX (and this is not as clear to me as when I originally performed this swap) caliper piston area was greater than the total area of the two pistons in the Toyota caliper which meant greater clamping force.

3) I wanted to avoid a wheel spacer at all costs, which would have been required if I used the Toyota calipers with my wheels.

[A. G. Olphart]

Well, I borrowed a scale, and my coil over 240Z strut with Terry's brake upgrade is 50 pounds. A complete stock 280Z strut and brakes is 52 pounds.

 

Exact numbers not guaranteed (it was just a bathroom scale), but it doesn't seem that the brake upgrade hurts unsprung weight at all. .

[2126]

I also did the 300ZX rotor/ 280ZX caliper front upgrade on my 1970. I had to have the rotors turned down to 10.55" diameter, to have proper clearance under the caliper. I'm using AXXIS Metal Master pads with S.S. brake lines. Would I call this an upgrade? Absolutely! Think about it....the 280ZX brake system was designed for a car that wieghs about 2850 lbs, uses standard pads and rubber lines. Now install this set-up on a 2300 lbs. car with the better pads and lines and you have a brake system that will woe-down your early Z way better that you might imagine. As Terry says in his write-up....these are great for a street driven car. I agree 100%!!! As for the rear, I used the 280ZXT rear calipers/ 280Z rotors. I forgot to mention....my rotors are all slotted. One detail I did on my front struts, that was not mentioned in the upgrade write-up, was....on the cast ears (on the strut)that the caliper mounts to I machined the sides, opposite the stock caliper mounting surface flat, so the spacers needed to center the caliper over the rotors would sit square. ( the 280ZX calipers require mounting to the opposite side of the cast ears that the stock calipers mount to).

[Psykovertible]

I would like more info on the spacers required by your setup. It seems simple and straight forward. I cannot afford to screw around too much cause other parts of the car are going to drain the heck out of me.

 

I got the initial idea....

 

FRONT

1) 4 lug 300ZX vented rotors

2) S-12W Toyota calipers from trucks

3) spacers ??

4) custom lines ??

 

REAR

 

1) early 280ZX caliper

2) late 280ZX rotor

3) custom bracket

 

what else cause i'm ready to buy the parts. I can buy almost everything from BAP here in Phx AZ and probably get a one time buddy hook up price.

[RedNeckZ]

The spacer, you will need will depend on what hub you have on your Z. On most 240Z's and early 260 Z's, you will need a 1/2" spacer. On late model 260Z's and 280Z's, you will need a .350/.375 spacer. You can get the spacers from alot of sites on the web. Or you can have it made at your local machine shop. Check on both ways and take the cheapest way you can. I am running a 280Z hub on my 240Z and had to use the .375 spacer, had it made by a local machine shop. If you want to make it yourself, just send me a address and I can send you the plans for both the front spacer and rear mounting bracket. Also on the front 300ZX rotors, I did not have to turn them down at all. Everything bolted right up. About the brake hard lines, you have to bend them to fit the new calibers. Just take your time and don't kink the lines. If you do, you can get new lines from most parts stores or the junk yard. I did stainless steel flex lines for the front and rubber flex lines for the rear. There is a control pressure valve fitting, you have to remove from the rear line. It is located on the body work above the rearend on the passenger side. It stops you from putting to much pressure on the rear brakes (drums). I removed it and bent the line over to the fitting and reattached it. Some people put a adjustable control fitting into the line so that you can adjust the pressure going to the rear brakes. I have found I didn't need it. Other then that, make sure you torque all your bolts down good and bleed your brakes. If you want the plans, send your address to Day Dreamer10020001@Yahoo.com I will be more then happy to send you the info you will need. Take care, Rich.

[Guest zfan]

Rich could you send/email me the plans/dimensions for the front spacer and rear bracket you mantioned in the brake upgrade section. I am upgrading my 240Z brake as it is having a difficult time stopping my 500 hp 383.

 

Thanks Mike

[Guest zfan]

Went to the wrecking yard today and found no older than 1984 Maxima's and noticed this one had drums in the back. In 1982-83 are you guys sure they ran rear discs and if so were they an option? I also found no 1982-83 200sx's but I have afriend who is going to look around for one that has the calipers I need.

 

Mike

[zcarnut]

Went to the wrecking yard today and found no older than 1984 Maxima's and noticed this one had drums in the back. In 1982-83 are you guys sure they ran rear discs and if so were they an option?

 

Only the Maxima sedans (IRS) had rear disc brakes. The station wagon Maxima used a solid axle in the rear with drums.

[Guest zfan]

Does anyone know of a reputable company that makes the spacers for the 240 hub/300zx rotor/Toyota caliper swap? If so I would be interested as I no longer have easy access to machine shop or equipment.

 

Mike

[RedNeckZ]

you can try WWW.Modern-Motorsports.com or WWW.Arizonazcar.com . Still looking for another address I had some where. Will post it as soon as I find it. Take care, Rich.

[RedNeckZ]

Here is some more addresses for you to try: WWW.PDKFabrication.bravepages.com , WWW.Fonebooth.com/brakes_zcar.html , WWW.JSKInnovations.com , WWW.FaithMFG.com , WWW.Betamotorsports.com and WWW.EMachineshop.com Hope you can find what you need, Rich.8)

[Guest zfan]

Thank you very much. I contacted Ross at Modern Motorsports and I may just go that way. I can buy the brackets for the rear conversion and the spacers for the front as well I have everything else but the brackets and spacers.

 

Thanks again for your help.

 

Mike