Disk Brake Upgrade Ideas for 77 s30

[Zerocell5688]

going to be sweet good Sir, look forward to seeing the photos

Yea me too

~J

[Zerocell5688]

Ok so with the last payment made now i just gotta hurry up and wait to get the parts and start the clean-up and prep work for install! Pictures coming once progress commences!

~J

[Six_Shooter]

I'm surprised this thread is on page two and no one has said anything about brake balance.

 

Putting 4 piston calipers all the way around will be VERY rear brake biased.

 

Under braking conditions, the weight of a vehicle transfers forward and more "weight" is being put on the front axle, and so more brake "power" is needed to actually apply an opposite force to the motion of the vehicle. Since the weight is transfered forward during braking conditions, this means that weight is "removed" from the rear axle and so less braking "power" is needed to apply the same amount of braking force to the rear axle. This is an overly simplified explaination, but I hope it starts to iilistrate the point.

 

This is the reason that the rear calipers and usually rotors are smaller than the front on the same car.

 

I have the Toyota 4 piston front calipers with non-vented rotors, along with the 280ZX rear disc swap, and my car stops well. I actually have the original master cylinder as well, and I don't find my pedal spongy at all. That will be at least in part due to the braided stainless steel flex lines I am using. I've only ever locked my brakes up once, in a panic situation, because the rest of the time the brakes work well enough to be able to modulate the brakes and come to a nice controlled stop, even in near panic situations. I'm not one that is not hard on thier brakes, but I do like to have upgraded brakes simply for the fact that it's easier to modulate a more "powerful" brake set-up than one that is just adequate.

 

I would suggest going with the vented front brakes though. The only reason I have the non-vented version on my car currently is because I bought the entire brake set-up from one person, and it was easier to just use what I got.

[Zerocell5688]

I'm surprised this thread is on page two and no one has said anything about brake balance.

 

Putting 4 piston calipers all the way around will be VERY rear brake biased.

 

Under braking conditions, the weight of a vehicle transfers forward and more "weight" is being put on the front axle, and so more brake "power" is needed to actually apply an opposite force to the motion of the vehicle. Since the weight is transfered forward during braking conditions, this means that weight is "removed" from the rear axle and so less braking "power" is needed to apply the same amount of braking force to the rear axle. This is an overly simplified explaination, but I hope it starts to iilistrate the point.

 

This is the reason that the rear calipers and usually rotors are smaller than the front on the same car.

 

I have the Toyota 4 piston front calipers with non-vented rotors, along with the 280ZX rear disc swap, and my car stops well. I actually have the original master cylinder as well, and I don't find my pedal spongy at all. That will be at least in part due to the braided stainless steel flex lines I am using. I've only ever locked my brakes up once, in a panic situation, because the rest of the time the brakes work well enough to be able to modulate the brakes and come to a nice controlled stop, even in near panic situations. I'm not one that is not hard on thier brakes, but I do like to have upgraded brakes simply for the fact that it's easier to modulate a more "powerful" brake set-up than one that is just adequate.

 

I would suggest going with the vented front brakes though. The only reason I have the non-vented version on my car currently is because I bought the entire brake set-up from one person, and it was easier to just use what I got.

Yea you def bring up a good point about the balance aspect and me and my other Z friend over here have been talking about this same point, the hows and why's of brake balance and design. I figure stocks in front and S13's in the back should be more than sufficienct with a 15/16 mas cylinder for my DD use. I just need to get some good pads for the front till i can get the money to go Vented! hey Six Shooter did you have to change your rim/wheel to fit the 4x4 non vented set up? I've heard alot of mixed things about this and i have to work on getting everything together in order so i don't work myself into a non runnin corner you know? I've got the 14" steelies with Z covers on them now till i can get my 16x7's.

~J

[Six_Shooter]

I had some steel "slot" type wheels when I first got my Z and swapped on the brakes, not the stock steel wheels, so I can't say that they will fit or not.

 

I currently have 280ZX 6 spoke wheels on my car, and the clearance is fine with them.

 

You could always, just unbolt the stock caliper, hang it out of the way on a coat hanger, or mechanics wire, bolt the Toyota caliper in place and set your wheel back on, to check for clearance. Snug up at least two of the lugnuts and spin the wheel to make sure there is no interferance.

[Zerocell5688]

You could always, just unbolt the stock caliper, hang it out of the way on a coat hanger, or mechanics wire, bolt the Toyota caliper in place and set your wheel back on, to check for clearance. Snug up at least two of the lugnuts and spin the wheel to make sure there is no interferance.

thats a Really good idea why didn't i think of that -facepalm- i'll have to get my hands on a kit and check it out. its starting to look like i'm just assembling a massive array of parts and one of these weekends i'm just gonna have a strip-and-swap-athon lol. yea i haven't met many people who still roll on the steelies, i kinda feel special in that one way lol

~J

[GaZed]

I installed my four piston calipers from a Toyota 4Runner onto my 280Z about 9 years ago. I went with vented rotors and had them cross drilled. The stopping power is incredible! I also installed a Wilwood proportioning valve just to fine tune it. Lastly, the larger brake cylinder.

 

For the rears crossdrilled 280ZX rotors IIRC. Apart from not having an ebrake it's a great setup

 

George

[JMortensen]

Putting 4 piston calipers all the way around will be VERY rear brake biased.

That's a pretty bold statement. I don't think it's true either. Look at AZC's brake setup for example. For years they ran 1.75" piston Superlites in front and 1.38" piston Dynalites in the back, I think the 6 piston fronts are still an option. You don't ever seem to hear about people complaining about the rears locking first. The kit comes with an adjustable proportioning valve in there and it seems to work for a lot of people. I HOPE it works, I'll be doing something similar on my car. Of course I'll have dual masters, so I can just go to a smaller rear master if I have trouble.

 

I have the Toyota 4 piston front calipers with non-vented rotors, along with the 280ZX rear disc swap, and my car stops well. I actually have the original master cylinder as well, and I don't find my pedal spongy at all. That will be at least in part due to the braided stainless steel flex lines I am using. I've only ever locked my brakes up once, in a panic situation, because the rest of the time the brakes work well enough to be able to modulate the brakes and come to a nice controlled stop, even in near panic situations. I'm not one that is not hard on thier brakes, but I do like to have upgraded brakes simply for the fact that it's easier to modulate a more "powerful" brake set-up than one that is just adequate.

I'm thinking you just haven't seen how they actually work when you do lock them up. I went to a driving school with a similar setup, 4 piston Toy fronts on solid rotors and 79 ZX rear disk with a ZX master and SS lines. They had us drive through a huge puddle and slam on the brakes to get the feel of locking them up. I was told by one of the instructors that my rears never locked even while driving through the puddle. This was with the stock prop valve gutted and an adjustable one on the back that was all the way open. After that I removed it entirely and it STILL didn't have anywhere near enough rear braking. After that I returned to stock front calipers and I was finally able to lock the rears first, and toned it down with the adjustable prop valve to get it where it should be.

 

I would suggest going with the vented front brakes though. The only reason I have the non-vented version on my car currently is because I bought the entire brake set-up from one person, and it was easier to just use what I got.

Definitely. The 4 piston front calipers with solid rotor only buys you a little more time before the pads overheat and the brake fluid boils. A vented rotor will really help to dissipate the heat and that's what you're looking for. VARA racers have to run the Toy vented setup and they do pretty well with it considering how powerful the cars are and how sticky the tires are.

[Six_Shooter]

That's a pretty bold statement. I don't think it's true either. Look at AZC's brake setup for example. For years they ran 1.75" piston Superlites in front and 1.38" piston Dynalites in the back, I think the 6 piston fronts are still an option. You don't ever seem to hear about people complaining about the rears locking first. The kit comes with an adjustable proportioning valve in there and it seems to work for a lot of people. I HOPE it works, I'll be doing something similar on my car. Of course I'll have dual masters, so I can just go to a smaller rear master if I have trouble.

 

*sigh*

 

Please go back and read the first post of this thread, you'll see why my "bold statement" is more than true.

 

*hint* The idea was to use the same calipers all the way around. No mention of prop valves, or any other tuning devices.

 

 

I'm thinking you just haven't seen how they actually work when you do lock them up.

 

Quite true, you know why? Because as I said I've only locked them up once, and guess what, I was IN the car when it happened, kinda hard to see how the wheels are locking up or which ones are locking up first.

 

I went to a driving school with a similar setup, 4 piston Toy fronts on solid rotors and 79 ZX rear disk with a ZX master and SS lines. They had us drive through a huge puddle and slam on the brakes to get the feel of locking them up. I was told by one of the instructors that my rears never locked even while driving through the puddle. This was with the stock prop valve gutted and an adjustable one on the back that was all the way open. After that I removed it entirely and it STILL didn't have anywhere near enough rear braking. After that I returned to stock front calipers and I was finally able to lock the rears first, and toned it down with the adjustable prop valve to get it where it should be.

 

I don't know about you, but I'm hardly ever at the need to lock up my brakes, I'm a driver that plans out and pays attention to what is going on around me, hense why I've, again, only locked up my brakes once on my 240. The braking is very good and controlled the way it is now, with no indication that the rears are lacking in performance. I've had several other cars that have had brake problems at one time or another and know when something isn't quite right. While I may want a bit more rear brake bias than I have now, the system works quite well as is. I'll be changing most of it this winter anyway, since I will be swapping to 5 lugs hubs, and will be doing the brake set-up a little differently than what I've seen other people do with the 5 lug swap, but now we are getting off topic here....

 

 

Definitely. The 4 piston front calipers with solid rotor only buys you a little more time before the pads overheat and the brake fluid boils. A vented rotor will really help to dissipate the heat and that's what you're looking for. VARA racers have to run the Toy vented setup and they do pretty well with it considering how powerful the cars are and how sticky the tires are.

 

This is part of the reason my brake system will be changing, in addition to the fact that my current rotors won't work well with the 300ZX hubs. That and I'd rather have vented rotors anyway.

[JMortensen]

*sigh*

 

Please go back and read the first post of this thread, you'll see why my "bold statement" is more than true.

 

*hint* The idea was to use the same calipers all the way around. No mention of prop valves, or any other tuning devices.

I was taking issue with YOUR statement, not the original post. The original post is wrong. Your statement is also wrong.

 

Quite true, you know why? Because as I said I've only locked them up once, and guess what, I was IN the car when it happened, kinda hard to see how the wheels are locking up or which ones are locking up first.

Fair enough. Also tells me that you can't FEEL if the rears are acting appropriately though. Don't feel bad though, I don't think 99% of the Z drivers out there can feel a bias issue, but that doesn't seem to stop them from proclaiming how great their brakes work and how they are properly biased. If you were able to adjust them to where the rears did lock first, and then back them off until the bias was correct, I submit that you would find a huge increase in the braking potential, and learn what it feels like to have proper bias. I did.

 

I don't know about you, but I'm hardly ever at the need to lock up my brakes, I'm a driver that plans out and pays attention to what is going on around me, hense why I've, again, only locked up my brakes once on my 240. The braking is very good and controlled the way it is now, with no indication that the rears are lacking in performance. I've had several other cars that have had brake problems at one time or another and know when something isn't quite right. While I may want a bit more rear brake bias than I have now, the system works quite well as is. I'll be changing most of it this winter anyway, since I will be swapping to 5 lugs hubs, and will be doing the brake set-up a little differently than what I've seen other people do with the 5 lug swap, but now we are getting off topic here....

When I was able to drive my Z last (~6 years ago) I was locking up the brakes at least once a month, but that's because I autoxed every month and did several track days a year, and I had a tendency to drive too deep into the braking zone. I would say that you are under the erroneous impression that your braking is very good and controlled, but in all likelihood the rears aren't doing what they should. Brake upgrades aren't as simple as saying bigger is better. If bigger isn't correctly biased, it will probably be worse than stock (at least until you run into temp issues). I would suggest that yours are probably worse than stock if they're like mine were. Mine improved SIGNIFICANTLY by going back to stock front calipers and keeping the ZX rear disks.

 

This is part of the reason my brake system will be changing, in addition to the fact that my current rotors won't work well with the 300ZX hubs. That and I'd rather have vented rotors anyway.

Good call. You might do something about the bias issue while you're at it.

[Zerocell5688]

Yea i really need to invest in an adjustable brake proportion valve before i get everything going and new brake line would probably be smart too.. *Sigh*

"Everything seems Tempting but nothing comes for Free," Or rather, super easy lol but its better to do it once the right way than to keep half assing it i think. Its like music, once you know it, you don't need to think about it, but until than its alot of factoring and preporations to make things go just right

~J

[Six_Shooter]

I was taking issue with YOUR statement, not the original post. The original post is wrong. Your statement is also wrong.

 

Well since my post was about this thread and what it was discussing it is was and still is absolutly correct. Agree to disagree, since you seem to think everyone has to share your views and opinions.

 

 

Fair enough. Also tells me that you can't FEEL if the rears are acting appropriately though. Don't feel bad though, I don't think 99% of the Z drivers out there can feel a bias issue, but that doesn't seem to stop them from proclaiming how great their brakes work and how they are properly biased. If you were able to adjust them to where the rears did lock first, and then back them off until the bias was correct, I submit that you would find a huge increase in the braking potential, and learn what it feels like to have proper bias. I did.

 

Holy bad assumptions, Batman.

 

You have no idea what my abilities are, or what I can or can not "feel", so now, you're just making yourself look more like an ass, remember the definintion of "assume".

 

I find it doubling entertaining that while you have never seen my car, you assume that it's not set up right, and isn't controlled under braking conditions. I'm interested to know how you can tell this from over the internet.

 

 

When I was able to drive my Z last (~6 years ago) I was locking up the brakes at least once a month, but that's because I autoxed every month and did several track days a year, and I had a tendency to drive too deep into the braking zone. I would say that you are under the erroneous impression that your braking is very good and controlled, but in all likelihood the rears aren't doing what they should. Brake upgrades aren't as simple as saying bigger is better. If bigger isn't correctly biased, it will probably be worse than stock (at least until you run into temp issues). I would suggest that yours are probably worse than stock if they're like mine were. Mine improved SIGNIFICANTLY by going back to stock front calipers and keeping the ZX rear disks.

 

 

Good call. You might do something about the bias issue while you're at it.

 

Again, you assume, that there is sometihing wrong with my brakes, and/or my biasing, I'm still trying to figure out how you "know" this.....

 

Oh wait, I guess that's because we have to go back to the fact that everyone must share your views and opinions....

 

I think we've gone through this already......

 

I'm finding this trend with some of the "senior" members, who some don't appear to even drive Z cars anymore, are trying to push away people, that are actually trying to help others, by claiming to know more than the people that are posting trying to help, a little disheartening, in that even when someone trys to help, no matter how correct the reply is, one of these "senior" members will come in and argue, some point that I'm still trying to figure out.

 

Why not, and this is just an idea, instead of trying to argue with one person, help out the subject of the thread? I dunno, maybe that's too idealistic?

 

I replied, because the idea of using the same caliper all the way around is not a good way to set up a braking system, and no one else had pointed that out.

 

I was also trying to point out why it was a bad idea, not just argue some minsicule point.

[Racer Z]

You two butting heads makes me laugh my ass off. Both of you make some good points, but you both take away from the discussion of GOOD BRAKES. Good Braking Habits is a good discussion, and should be in it's OWN thread.

 

I (we) are setting up a track car and I (not we) am thinking about using the same size vented rotors on all fours along with matching 4-piston calipers (the 300zx vented front disk and Toyota 4x4 calipers). My thinking includes a dual master set-up with a balance bar (no need for a proportioning valve). Probably a 1 inch master on the front and a 7/8 rear. But, there is a lot of unknown for me with this set-up. (Our track does not need an E-brake). For the purpose of being able to run with VARA and certain other clubs, I'm limited to what I can modify and how I can modify it.

 

Simply adding more pistons at the rotor won't increase your braking power, it applies the load more evenly to the pad. More pistons usually mean a larger pad can be used; a larger pad means more braking power. A larger piston in your master also means more braking power regardless of what you do to the calipers / pads.

 

All of the (stock) 280ZX's and 300ZX's have larger rear disks and more rear pad area except some of the turbo models.

 

Good looks don't get my car across the finish line any quicker. The winner of the race sets the new precedent for "Looks Cool!"

[HLS30-08077]

Does any one on here have pics of their 79' to 81' 280ZX rear disc brake swap into an S30. I need to see the Stainless brake lines you used and how they fit. Can I just buy the regular Earls SS lines from Motorsport for my 260Z and still use them with the ZX rear disk brakes???

 

I need pics people, Please!!! I'm a visual kinda guy.

 

Dave

[GaZed]

Does any one on here have pics of their 79' to 81' 280ZX rear disc brake swap into an S30. I need to see the Stainless brake lines you used and how they fit. Can I just buy the regular Earls SS lines from Motorsport for my 260Z and still use them with the ZX rear disk brakes???

 

I need pics people, Please!!! I'm a visual kinda guy.

 

Dave

Hi Dave,

 

I did this some 12 years ago, and it was a great modification. As I recall I had to fabricate some short 90 degree brake lines at the caliper end. The Earl lines from Motorsports are what I used...no problem. The main steel brake lines needed to be rerouted. The bracket to which the clip attaches the brake line was either unbolted or cut off as you will see in the pictures. Some time was spent moving that brackets around so that it would not interfer with the wheel and half-shafts when the full weight of the car was applied to the wheels. Once installed, the new lines made a tremendous improvement. I since have heard many good thing about Goodridge teflone steel braided lines. Here are some pictures I hope they help!

 

Best regards,

George

[HLS30-08077]

Thanks George, That's a start.

 

Dave

[h4nsm0l3m4n]

Here's a couple pics of my setup sorry theyre a little dark. I'm using 83 zxt rotors and calipers. Not exactly the same as the 81 calipers I think, but close. I used a set of Russell SS lines (pn 686550) and had to buy a male to male adapter for the hose to fit straight to the caliper. Im pretty sure you should be ok with the MSA kit.

 

 

[Avernier]

which mounting brackets did you use?

[HLS30-08077]

OK, here's what I got. I bought the 79' to 81' 280ZX adaptors and picked up the 79' 280ZX calipers from the Pull-A-Part for $6.50 each (love pull-a-part) pads were $12 for the rears and the adaptor I got for $90 cause someone changed their mind.

 

Here are the pictures. You can see on the last pic that I obviously need a 90* to aim the line upward towards the main brake line on the body. I'm thinking, maybe a plate weded to the top of the brake bracket to hold the hard line, then the SS flex line from there to the body. Maybe? Opinions?

 

So do I need to cut off the ebrake bracket and weld on the stock one in that place to get it to correctly and at the correct angle? The cut/bent line is just to keep the inlet clean and dirt free. just temporary.

 

Dave

[HLS30-08077]

OK, so here's what I did.... Took a while but I got the OEM bracket off, loaded the ebarke cable onto the stock bracket and figured out where I wanted it. I went for the old 2 finger spacing and it looks and operates properly. I should have the rotors in by friday and we'll see how they look.

 

But I still gotta order the stainless lines to mock up the calipers hard lines and see if the banjo is an option or a better bet. Also crossed the E-Brake cables over to take up the slack. I can pull the cable by hand, from in front of the diff, without it binding. So pulling the handle should be very affective.

 

On the 4th picture, the suspension is fully dropped and when it comes back up, will hit the stock brake bracket. So I need to cut it off and move it back towards the rear of the car so the SS line and the caliper will clear the bracket.

 

Dave.