280zx Arizona Z Car BBK Write-Up/Review

[83turbo280zx]

Ok so I've gotten to the point where bigger brakes is becoming a bigger and bigger issue with my car. I'm able to accelerate very fast, need to slow down just as fast so I bought the "entry level" Big brake kit from Arizona Z Car. Its the Wilwood 4 piston caliper w/ the 12.2" diameter rotor. I paid $826 shipped to my door. Came in the box, was very well packaged, Dave was very informative on the phone and very friendly. Had a little hiccup on getting the product shipped out to me, but wasn't his fault, just the way things go when running a business of your own. Nonetheless I was impressed with the packaging and quality of the parts right out of the box.

Now his website states that these brakes will clear 15" wheels minimum. This is true, just not for the stock 15" turbo wheels on the 280zx. They have a drop center that will hit the front of the caliper. So you can either get 1" thick wheel adapters, or do it right and get bigger wheels. So i opted for some 16x8 XXR 532s which I am very pleased with. Will have another write up on how to modify the factory center caps to fit the XXR wheels. Anywho, the installation is very straight forward if you're handy with tools. If not here are a few things that you may want to take note of for a smooth install.

Of course with upgrading wheels, I had to get longer wheel studs because the stock mag wheel lugs will not work with aftermarket wheels. Tuner lugs don't thread in far enough with the stock studs. The rear studs are longer than the front studs on the 280zx, so you won't have to upgrade the rears if you're on a budget. I did all 16. I used Dorman part # 610-320 from O'reilly Auto parts, they are approx 12-13mm longer than the stock ones.

Remove all the old brake stuff INCLUDING the splash shield, Keep or discard this depending on your preference. Use an impact driver $11.99 @ O'reillys, this way the rusted bolts will come out without stripping the phillips head.

Once you get the rotor swapped over to the hub, install the caliper bracket bolts into the spindle with the bolt head facing outward towards the rotor. If you do this the other way, the lock nut will hit the rotor and wont turn.

Use one washer with the supplied bolts.

Once you get the bolts in, put the rotor on, pack the bearings and tighten. You will now push the bolts back into the rotor so you can get the caliper bracket and caliper assembly (leave them bolted together) onto the spindle. Before you put the caliper assembly on, put one washer on the other side of the bolt on each bolt, to shim the caliper assembly and center the caliper. You also want to remove the brake pads as this makes it easier to get into place. Tighten everything, then run your brake line, and put your brake pads in.

Bleed all the air from the top two bleeders. There is no sense in bleeding the bottom bleeders other than to get clean fluid through the caliper as air rises and you will never get air out of the bottom bleeders.

Get everything bolted, tight, and bled, and go for a drive.

I noticed right away the HUGE difference in braking ability. It grabs MUCH better than the stock boat anchor system. I had a problem with it pulling hard left under heavy braking with the stock system. Between the stiffer braided lines, and the fixed caliper, There is definitely more braking force for less pedal effort. You will definitely be able to out-brake most cars on the road so be careful when braking in traffic lol. It will require a lot less pedal effort to get the same amount of braking as the old stock setup.

I am VERY satisfied with the results of this brake setup and wouldn't flinch to suggest this to anyone looking into a brake upgrade. I feel that brakes should be something you spend the utmost attention and care to. You should NEVER skimp out on something that could save your life one day. One of the biggest reasons I picked this brake setup over the Toyota 4x4 brake upgrade. I've read numerous reviews over it being somewhat of a spongy setup and having to play with proportioning and everything, I said screw that. Dave has been working on Z car brake systems for a long time and he definitely knows what he's doing. Would EASILY recommend this brake upgrade to any Z car owner out there.

[Nigel]

 

 

I am VERY satisfied with the results of this brake setup and wouldn't flinch to suggest this to anyone looking into a brake upgrade. I feel that brakes should be something you spend the utmost attention and care to. You should NEVER skimp out on something that could save your life one day. One of the biggest reasons I picked this brake setup over the Toyota 4x4 brake upgrade. I've read numerous reviews over it being somewhat of a spongy setup and having to play with proportioning and everything, I said screw that. Dave has been working on Z car brake systems for a long time and he definitely knows what he's doing. Would EASILY recommend this brake upgrade to any Z car owner out there.

 

 

 

Great write up! I'm ordering the AZC brakes for my 240Z, so I'm happy to hear a positive review. I currently have the 4 cyl 4x4 brakes with the 300ZX vented rotor up front. However, there's really nothing wrong with them though. I just want something lighter with more power/better heat dissipation. Can you point to the reviews that claim the 4x4 brakes are spongy? There's nothing about the design that would make them inherently spongy. I suspect it has a lot to do with the master cylinder size that is being used.

 

Also, you may not be aware, but if you've done nothing with your rear brakes, the front/rear balance on your car is now going to be out far more than it would be with the 4x4 setup. If your Wilwood front calipers have the 1.75" pistons, that's bigger than the pistons in the 4x4 caliper. Also, you now have a much larger diameter rotor. You'll get more brake torque on the front wheels than the 4x4 setup, and way more than stock. So, in reality, you need to "play with proportioning" more so than ever. Stopping distances can actually be longer with overly front biased brake systems.

 

Nigel

[83turbo280zx]

"Also, you may not be aware, but if you've done nothing with your rear brakes, the front/rear balance on your car is now going to be out far more than it would be with the 4x4 setup. If your Wilwood front calipers have the 1.75" pistons, that's bigger than the pistons in the 4x4 caliper. Also, you now have a much larger diameter rotor. You'll get more brake torque on the front wheels than the 4x4 setup, and way more than stock. So, in reality, you need to "play with proportioning" more so than ever. Stopping distances can actually be longer with overly front biased brake systems.

 

 

Well i read into that with the 4x4 setup. Dave @ AZC said this was a bolt on and go setup. Especially with the ZX 15/16" master. I'd imagine the same amount of fluid displacement would take place between 4 smaller pistons versus one big piston on the ZX stock calipers. The 4x4 calipers however are massive. Dave does offer an adjustable proportioning valve for i'm guessing the older Z's that originally had drum brakes. But since mine came factory with 4 wheel disc, it hasn't been an issue. It doesn't nose-dive like an unproportioned vehicle would behave. Its extremely smooth, great engagement, very positive pedal feel and no grabbing or locking up issues. I read a write-up that dave wrote a while back about fluid hydraulics. It really made sense of the whole bigger isn't necessarily better. Just because the piston is a certain size has no indication of the actual fluid power behind it, which is what makes this kit superior to the 4x4 brakes.

[Nigel]

The 280ZX front calipers have a 2.36" dia front caliper piston, which works out to 4.37 square inches of surface area. This compares to 2 x 1.75" pistons (only half the pistons are needed for comparison), for a surface area of 4.81 sqin. So the Wilwood caliper does have a larger volume to fill. But not so much that a larger master cylinder is required.

 

Combine that increase in piston surface area with an increase in rotor diameter (9.92" to 12.2"), and the Wilwood fronts produce a ~50% increase in brake torque over stock though! Just because you have rear disk brakes isn't the end of the story. You've gone from a stock ZX front/rear brake torque ratio of ~64/36, which is what the Nissan engineers felt was acceptable, to a front/rear brake torque ratio of 72/28. Those numbers I'm providing are with full line pressure to the rear brakes. The stock proportioning valve throttles back the rear line pressure, so in effect, the front/rear ratio will be even more front biased with the Wilwood setup if you still have the stock prop valve in place. By comparison, using the AZC front AND rear kits, you get a 62/38 split which is even more rear biased than stock! This isn't even taking into account pad compounds, which also have a significant impact. Can you provide a link to Dave's write up on fluid hydraulics? Piston sizing has everything to do with fluid power. That's the whole basis of hydraulic systems. But you have to consider the source and destination.

 

Now, all this doesn't mean that what you have doesn't work. But, short of a full rear upgrade, I'd bet braking distances could be improved with more rear line pressure at the very least, and even more so with an increase in rear pad friction if available. You need load transfer to the front wheels to take advantage of big front brakes, and you can't get that transfer with insufficient rear brake torque. BTW, a lot of those aftermarket so-called "big" front brake kits you see on a lot of cars, don't actually generate any more brake torque than the stock setup. The calipers often look huge, but they have tiny little pistons in them. This is done in order to maintain the factory front/rear ratio, otherwise, braking distances would be worse.

 

Either way, still a great kit. Sounds like you're really enjoying it. I can't wait till I get mine!

 

Nigel

[83turbo280zx]

The 280ZX front calipers have a 2.36" dia front caliper piston, which works out to 4.37 square inches of surface area. This compares to 2 x 1.75" pistons (only half the pistons are needed for comparison), for a surface area of 4.81 sqin. So the Wilwood caliper does have a larger volume to fill. But not so much that a larger master cylinder is required.

 

Combine that increase in piston surface area with an increase in rotor diameter (9.92" to 12.2"), and the Wilwood fronts produce a ~50% increase in brake torque over stock though! Just because you have rear disk brakes isn't the end of the story. You've gone from a stock ZX front/rear brake torque ratio of ~64/36, which is what the Nissan engineers felt was acceptable, to a front/rear brake torque ratio of 72/28. Those numbers I'm providing are with full line pressure to the rear brakes. The stock proportioning valve throttles back the rear line pressure, so in effect, the front/rear ratio will be even more front biased with the Wilwood setup if you still have the stock prop valve in place. By comparison, using the AZC front AND rear kits, you get a 62/38 split which is even more rear biased than stock! This isn't even taking into account pad compounds, which also have a significant impact. Can you provide a link to Dave's write up on fluid hydraulics? Piston sizing has everything to do with fluid power. That's the whole basis of hydraulic systems. But you have to consider the source and destination.

 

Now, all this doesn't mean that what you have doesn't work. But, short of a full rear upgrade, I'd bet braking distances could be improved with more rear line pressure at the very least, and even more so with an increase in rear pad friction if available. You need load transfer to the front wheels to take advantage of big front brakes, and you can't get that transfer with insufficient rear brake torque. BTW, a lot of those aftermarket so-called "big" front brake kits you see on a lot of cars, don't actually generate any more brake torque than the stock setup. The calipers often look huge, but they have tiny little pistons in them. This is done in order to maintain the factory front/rear ratio, otherwise, braking distances would be worse.

 

Either way, still a great kit. Sounds like you're really enjoying it. I can't wait till I get mine!

 

Nigel

 

Yes i am really enjoying it! I will try and find those links, i found them through different Z forums when i was researching months before i bought the kit. Anywho, i was planning on using a z32 rear caliper setup in the rear, i found someone that bolted it right on to the factory control arm, i haven't mocked it up yet to see if it uses the stock rotor, or uses the z32 rotor re-drilled, and what pad selection. But yes i will eventually attack the rears too and I can agree with you on the basis that front brakes do you no good if you leave the stock rears on. Although the current bias is more than acceptable, there's never anything wrong with further improvements

[Nigel]

Believe it or not, but according to the math, the Z32 rear brakes would actually be a step backwards! The rotor is bigger, but the caliper only has a 38mm piston, which is 5mm smaller than the S130 rear caliper. So, the Z32 rear brakes actually generate less rear brake torque than the S130! 

 

I'm working on something right now for S30's that has an integrated parking brake and can work with a vented rotor between 11.5" and 13" in dia. It would probably translate over to the S130's with a few design adjustments. That's a few months away though..

 

Nigel

[Leon]

It doesn't nose-dive like an unproportioned vehicle would behave.

 

  What makes you think that's how an "unproportioned vehicle" behaves?

 

Nose-diving means there is (longitudinal) weight transfer. Longitudinal weight transfer to the front of the car ("nose-dive") is caused by a braking force. More braking force equals more nose-diving.

 

If your nose dives less than before, it's telling me that you have less braking force, not more.

[83turbo280zx]

Believe it or not, but according to the math, the Z32 rear brakes would actually be a step backwards! The rotor is bigger, but the caliper only has a 38mm piston, which is 5mm smaller than the S130 rear caliper. So, the Z32 rear brakes actually generate less rear brake torque than the S130! 

 

I'm working on something right now for S30's that has an integrated parking brake and can work with a vented rotor between 11.5" and 13" in dia. It would probably translate over to the S130's with a few design adjustments. That's a few months away though..

 

Nigel

 

Hmm, even with dual pistons? Well I may have to reconsider what I'm doing for rear brakes then. maybe for now EBC pads and drilled/slotted rotors will suffice in the rear until I can do more research.

 

  What makes you think that's how an "unproportioned vehicle" behaves?

 

Nose-diving means there is (longitudinal) weight transfer. Longitudinal weight transfer to the front of the car ("nose-dive") is caused by a braking force. More braking force equals more nose-diving.

 

If your nose dives less than before, it's telling me that you have less braking force, not more.

 

Well maybe what you're saying nose diving is and what i'm saying it is are different. I'm referring to a vehicle that has no rear brake actuation at all. I've driven several s30s with 4x4 brakes up front, stock drums in the back w/ the stock master and stock proportioning valve that had no rear brake actuation at all after the swap. Now whether its because a. introducing clean fluid into the brake system caused the proportioning valve to hang and send all braking power to the front, or there's more fluid displacement in the fronts now that the rears don't grab until after the fronts start to. Who knows. Or drive any tahoe or chevy truck that still has rear drums that are WAYY out of adjustment (which essentially creates a WAY greater front brake bias). Thats what I was getting at. The nose dive created from the front brakes actuating before the rears because of a severly front biased system.

[83turbo280zx]

and i also wasn't saying it nose dove before i put these Big brakes on, i was just saying it doesn't nose dive like a severly front biased brake system would.

[Leon]

Well maybe what you're saying nose diving is and what i'm saying it is are different. I'm referring to a vehicle that has no rear brake actuation at all. I've driven several s30s with 4x4 brakes up front, stock drums in the back w/ the stock master and stock proportioning valve that had no rear brake actuation at all after the swap. Now whether its because a. introducing clean fluid into the brake system caused the proportioning valve to hang and send all braking power to the front, or there's more fluid displacement in the fronts now that the rears don't grab until after the fronts start to. Who knows. Or drive any tahoe or chevy truck that still has rear drums that are WAYY out of adjustment (which essentially creates a WAY greater front brake bias). Thats what I was getting at. The nose dive created from the front brakes actuating before the rears because of a severly front biased system.

 

Nope, nose-diving is nose-diving.

 

Would you agree that a car will dive whether the rear brakes or front brakes are actuated?

 

What I'm getting at, is it doesn't matter which axle does the braking. The amount of weight transferred to the front axle is dependent upon total braking force.

 

How much the nose dives has to do with spring rates, suspension geometry, and available braking force.

Edited March 6, 2013 by Leon

[Leon]

and i also wasn't saying it nose dove before i put these Big brakes on, i was just saying it doesn't nose dive like a severly front biased brake system would.

 

And my contention is that a severly front-biased system will not dive more than a properly biased one. Your statement is a non sequitur.

 

Not trying to rain on your parade here, just clearing up some facts...

[Nigel]

Hmm, even with dual pistons? Well I may have to reconsider what I'm doing for rear brakes then. maybe for now EBC pads and drilled/slotted rotors will suffice in the rear until I can do more research.

 

Assuming equal piston diameters, a single piston floating caliper generates the same clamping force as two opposed pistons.

 

I personally wouldn't bother with drilled rotors. Maybe slotted. Neither will improve brake torque. I'd invest in an adjustable proportioning valve and experiment with more rear line pressure (In addition to different rear pad compound).

 

Nigel

Edited March 6, 2013 by Nigel

[83turbo280zx]

 

And my contention is that a severly front-biased system will not dive more than a properly biased one. Your statement is a non sequitur.

 

Not trying to rain on your parade here, just clearing up some facts...

 

I understand where you're coming from, but i've personally seen and fixed them in the field. You get a car that doesn't have rear brake actuation, it WILL indeed nose dive harder than if the rear brakes were working properly. The rears grab first so you don't get that OH shit dive, i've dealt with it numerous times on several trucks with drum brakes. Sure spring rates and everything play a factor in it, but to say that rear brakes not actuating won't cause a car to dive is false, I've SEEN it, over and over again.

[Leon]

I understand where you're coming from, but i've personally seen and fixed them in the field. You get a car that doesn't have rear brake actuation, it WILL indeed nose dive harder than if the rear brakes were working properly. The rears grab first so you don't get that OH shit dive, i've dealt with it numerous times on several trucks with drum brakes. Sure spring rates and everything play a factor in it, but to say that rear brakes not actuating won't cause a car to dive is false, I've SEEN it, over and over again.

 

I'm coming at it from a physics perspective. Anecdotal evidence doesn't have much merit unless you actually measured the amount of nose-dive vs. braking distribution (at a given braking force)?

[slownrusty]

Great post.  This is on my list for my ZX and will certainly purchase from Dave.

[redzedturbo]

please post a pic of those wheels on your car! I was thinking of getting a set in 16 by 8 but have not ever seen them on a zx please! killer brakes by the way.

[Jordon]

Yes i am really enjoying it! I will try and find those links, i found them through different Z forums when i was researching months before i bought the kit. Anywho, i was planning on using a z32 rear caliper setup in the rear, i found someone that bolted it right on to the factory control arm, i haven't mocked it up yet to see if it uses the stock rotor, or uses the z32 rotor re-drilled, and what pad selection. But yes i will eventually attack the rears too and I can agree with you on the basis that front brakes do you no good if you leave the stock rears on. Although the current bias is more than acceptable, there's never anything wrong with further improvements

 

Have you thought about using the AZC Rear brake setup?

4 piston caliper, 12.2" rotor, 

[83turbo280zx]

please post a pic of those wheels on your car! I was thinking of getting a set in 16 by 8 but have not ever seen them on a zx please! killer brakes by the way.

Thanks buddy, here are the before/after pics

 

Before

 

After

 

 

 

Have you thought about using the AZC Rear brake setup?

4 piston caliper, 12.2" rotor, 

I have thought of it yes, but its not in the budget at the moment. I would like to eventually get his rear setup as stated above it will put the proportioning back to close factory specs. I just need to come up with another $800 lol

[ZUL8TR]

The front & rear set-up from AZC are on my Want List, as is a proportion valve. I do wish he would sort out the parking brake. Its one of the reasons I have been holding off. Bummed I can't use my ZXT wheels for now. I wanted to stagger the new brakes and new wheels over a few months. I guess that means wheels first, brakes later. 

[83turbo280zx]

The front & rear set-up from AZC are on my Want List, as is a proportion valve. I do wish he would sort out the parking brake. Its one of the reasons I have been holding off. Bummed I can't use my ZXT wheels for now. I wanted to stagger the new brakes and new wheels over a few months. I guess that means wheels first, brakes later. 

 

You can use the stock ZXT wheels, but you will need about a 1" thick hub spacer. All you will need to do is clear the drop center on the inside of the wheel, then they will clear. But for the price of 4 GOOD hub spacers, you could be more than half way for a set of XXRs minus the tires lol.