Caliper Weights

[bertvorgon]

I would beleive that. I would say on that type of track, with a high speed potential. my brakes would likely fade out too. The water sprayers work very well, for systems that are marginal for size.

[jeffball610]

I know of Mario's Brembo package, but I'm not rich. Those things are pretty huge though. What is the advantage to running such a large brake package? Obviously running that fast at Luguna Seca is a testament, but what about those of us with lower aspirations? Is the 280ZX caliper enough, or should we step up to something more substantial? For my budget, I'm basically looking at Toyota and Z32 calipers. I suppose I could adapt the 280ZX calipers to my 5 lugs, but would I want to?

I know brake pad composition is a huge thing and you should always run race pads at the track and street pads on the street. The Brakeman kit looks impressive as does the Willwood stuff. It's great to hear some first hand knowledge of the product in extreme racing conditions to make an informed decision between those two. Are there any other considerations we should take into account when selecting the proper brake package?

"Will it fit under my wheel?" is one of the most asked questions since a lot of guys run 13-14" wheels. A brake proportioning valve I would think is a must since we're usually mixing and matching brake components. I currently have a 15/16 Brake Master Cylinder since I'm running Z31 rear disks. A larger MC is a must when running rear disks on these cars correct? Everyone has a preference on brake pedal travel, but about how large of a MC should you run with some of these braking packages? I know a lot of guys run the Tilton set (dual reservoir for racing) and what size is it? Most of us can't run a brake booster, so should we compensate with a larger MC or is there something else?

I think a lot of this info would be nice as a sticky in the FAQ section. I'm sure this info is on these forums, but it's so spread out that it takes days to read through posts to get any concrete answers.

[okayfine]

Obviously running that fast at Luguna Seca is a testament, but what about those of us with lower aspirations? Is the 280ZX caliper enough, or should we step up to something more substantial?

Jeff, you haven't really supplied anything to judge by. "Lower aspirations" than full-on hooning around Laguna Seca covers a lot of ground. Are you building at track car, a race car, a street car? A combination? If so, what combination (percentages) and what would be your home track?

For my budget, I'm basically looking at Toyota and Z32 calipers. I suppose I could adapt the 280ZX calipers to my 5 lugs, but would I want to?

Likely not. If you have to make an adapter bracket anyway, why stick with the 280ZX caliper? Between the boat-anchor Toyota caliper and the aluminum Z32 caliper, I'd say there's only one choice, being the Z32 aluminum caliper.

It's great to hear some first hand knowledge of the product in extreme racing conditions to make an informed decision between those two.

Which is applicable if you're going to be using your car in similar extreme racing situations.

Are there any other considerations we should take into account when selecting the proper brake package?

Cost, effectiveness, maintenance interval (Wilwoods don't have seals and while not a huge deal, brake fluid flushes would need to be increased over a sealed caliper, for instance), fitment, parts availability, pad availability, pad cost, connections (Wilwood has a different thread in the caliper compared to Datsun 10x1.0), etc.

"Will it fit under my wheel?" is one of the most asked questions since a lot of guys run 13-14" wheels.

I ran that 11" disc/Wilwood setup under 14" wheels.

A brake proportioning valve I would think is a must since we're usually mixing and matching brake components.

I think a properly planned system can work without a proportioning valve. For those who seem to mention them a lot, I don't think they've really given much thought to the design of their new system. For example, you can get the Wilwood calipers with a few (three?) different size piston bores. You'll need to do math to figure what will work best with regards to balance.

I currently have a 15/16 Brake Master Cylinder since I'm running Z31 rear disks. A larger MC is a must when running rear disks on these cars correct?

No, it's not a must. It depends. As long as the master can move enough fluid to fully actuate the brake system, different masters will only vary the feel of your brake pedal. Simplified, but running rear discs has been done on every size master, 3/4, 7/8, 15/16.

so should we compensate with a larger MC or is there something else?

A larger master cylinder isn't going to give you "stronger" brakes. A larger MC, all other things being equal, will give you "weaker" brakes because the pressure you exert at the pedal will be less at the brake pad.

A power booster doesn't even give you stronger brakes (if we're measuring stopping distances). Just additional (vacuum-supplied) assistance to press the brake pedal.

[bertvorgon]

good thought on the need for "seals" on the street. I have run for a zillion years with no problems, but, my car is pretty much good weather only.

Your right, pedal effort can be an issue. I put a 2" section in my brake pedal, for both the increased leverage, and to get the pedal lower for heel and toeing. I use the 15/16" master.

I have more than enough leverage to both "feel" the brakes under extreme use, and, to lock the things for ever and a day. Do not discount the need for a subtle pedle touch, or feel. at least for me, when on the threshold of cornering and braking, it's nice to be able to hold that, without the risk of having to press so hard it locks up.

personally, from my race experience, for 25+ years of racing, with this combo, I have had more than enough brakes, except for the most extreme road race situation. is it the best...well, at leat for me it has been more than adequate for what I have done with my car, Solo, Hillclimbs, some road race, Cannonballs, Scenic cruises, etc.

If I was to do anything now, given that i have no intention to really run 13" wheels anymore ( due to tire choice and availability) I would likely go with some thing bigger ( on the front), as long as the weight penalty was not really great.

Also, when going to a bigger caliper...make sure you can get a soft enough pad for the street.

[jeffball610]

This is all great info.

As far as my setup, I stated that I planned to run about 90% on the street only seeing the occasional track day. I think pad selection would be the biggest difference between street and track though at this point.

As far as the MC goes, I was under the assumption that the larger it is, the more fluid it can push. Meaning less pedal effort to get the same caliper movement as a smaller MC. And I understand that the booster only gives a "boost" in pedal effort, not actual increased braking. I was asking to make it clear that there would be enough fluid from the MC to push 4 piston calipers up front and single piston disks out back without the assist of a brake booster.

So in looking at the "economical" choices, 280ZX would be the most straightforward for the average street car. I don't think that the 4 piston Z32 calipers will be too much for the street, but as bertvorgon stated, I would need a soft pad. I'm assuming that with the combination of a 15/16 MC and 4 piston calipers, that it would be pretty easy to lock up the brakes on the street, but not overkill for track days when the hard braking is really necessary. Is that a fair estimate or is it really just overkill in all aspects?

What other "economical" choices are there for brake upgrades? My Z31 rear disk upgrade is not a bolt on affair. I was in the process of the Maxima/200SX upgrade before I ditched that to run 5 lug hubs. Obviously there is still a lot of measuring to do to get the proper disks for each application and getting custom brake lines run. What other considerations should we take into account when putting this stuff together? Anyone got a good source for metric tube nuts? (to fit hard brake lines to other brake components)

[bertvorgon]

Don't think of it as "easy" to lock the brakes. What a good system should have, no matter what size of caliper rotor combo, is the ability of the driver to be able to push relatively hard ( and relative is just that) with a feed back from the brakes/tires, THAT YOU CAN FEEL, just before incipient lockup. Think about the real world, or race world.
You do not want something that locks up when you breathe on the brakes, otherwise, your tires will be flat spotted, you will never get into a corner fast, under braking, etc.. By having to push with some force, it takes the sensitivity out of the brake pedal, coupled with the choice of pad material. Having the rears ( I'm talking rear discs here), with enough rear bias, makes a 510 quite spectacular under braking. Most of the manufacturer's of both calipers and pads, tend to have a good range of pads. The pad, which of course is transmitting it's grip through the rotor, and then the tire, should be chosen for it's ability to give that feel in quite a lineal fashion, as it comes up through it's heat range. You can usually find graphs that show their ramp. My pads, ramp up quite fast, as they near their optimum temp range, at the top of that range, then they seem to level out, at least to the point that I have never taken them to fading. I run very good brake fluid, maybe overkill for the street, but, you never know!

Your tires grip will effect how the brakes feel too, as they will not be able to impart that true stopping power. Lower stick tires will just make your car feel like the brakes are not working, thus making you THINK that they are crappy. I guess what I am saying is the grip of the tires can dramatically effect the braking of the car, no brainer for sure, but, untill you have been on something really sticky, don't short change your brake system, when it can be the tires fault. Do not expect good brakes with the rubber lines, we all know that. Make sure the wheel bearings are good and tight, as pad knock back can make you think the pedal is mushy, or have more travel, or require two pumps. Rotors must be true, other wise, read last sentence.

As ok fine said, a bias valve can be worked around, but, I am glad I have mine. For different types of events, I can change my bias, as temperatures and severity of required braking change. For example, for Solo use, I run a ton of rear bias, where, if I happen to get too much rear brake, and I spin out, it won't kill me. And the greater rear bias helps set the car up going into a corner, to help change from corner entry understeer to oversteer slightly. Then, for the hillclimbs, where the speed was much, much higher, but still cold brakes, I would back off the bias to the front, decreasing the penchant for both rear lock up and oversteer, as the rear gets light, and you turn into a fst corner. A member on this site has a 510, who's previous owner was warned to back of the rear bias, before running the Hill. He did not, and ended up putting it off in Turn 1, as the rears locked, and spun him off. You get the idea at any rate. So, while you can get away with a system without bias, it sure is nice to have, as another tuning tool in the handling of the car. Brakes after all are part of the whole handling package. Just some thoughts at any rate.

Oh, an interesting story also:

Waaayy back, in the early 80's, Andy and I experimented with our own pads. We had a local brake shop take a variety of our pads, street/ and race, then cut a section out, across the pad. Then, we had them put in Boeing 747 pad material, that they were able to get! Holy crap, those were the most fantastic brakes we had in those days, just before the days of carbon fiber and other pads were just starting to come out. We still talk about that. I had a set in my Honda Civic wagon, which I ran at track days, very cool. Just as the factory material would be fading, that 747 stuff was starting to come up to temp. I could survive a track day, then still had brakes in the rain in good ole B.C.

[510Martinez]

This is all great info.
Anyone got a good source for metric tube nuts? (to fit hard brake lines to other brake components)

Napa.

[okayfine]

As far as my setup, I stated that I planned to run about 90% on the street only seeing the occasional track day. I think pad selection would be the biggest difference between street and track though at this point.

I wouldn't run anything more than the 280zx stuff, in that case. Cheap, available, all the braking capacity you need. You could also research the differences between the ZX stuff and the S12 stuff.

You can always upgrade should you find the need, but I don't think you will.

As far as the MC goes, I was under the assumption that the larger it is, the more fluid it can push.

You move more fluid, but you end up with less pressure at the pad. It's a hydraulic thing.

I was asking to make it clear that there would be enough fluid from the MC to push 4 piston calipers up front and single piston disks out back without the assist of a brake booster.

Provided your system (BMC, calipers) is sized correctly, you could move 20 pistons without a booster.

I'm assuming that with the combination of a 15/16 MC and 4 piston calipers, that it would be pretty easy to lock up the brakes on the street, but not overkill for track days when the hard braking is really necessary. Is that a fair estimate or is it really just overkill in all aspects?

Jeff, you're not getting it. Why would a 15/16 and 4-pots be easier to lock up? You're reducing pressure at the pad, all else being equal.

I had that setup on the car I mentioned on page one. Dead, wooden pedal. You really had to put your leg in it to get large deceleration. This is with discs in the rear. It would have been much better with a 7/8" BMC and/or a different selection of piston bore size for the 4-pots.

Bigger is not necessarily better.

[okayfine]

As ok fine said, a bias valve can be worked around, but, I am glad I have mine. For different types of events, I can change my bias, as temperatures and severity of required braking change.

Keith, this is proper use of the bias valve, as you don't need me to confirm.

My comments were meant to suggest that using a bias valve to get around the drawbacks of a poorly-thought-out brake system (a band-aid, if you will) was improper use of a bias valve.

[bertvorgon]

Thanks, I did know what you meant.

Brakes, because of the many combinations that we have access to, become one of those great mysteries that can totally befuddle us. I wish I was better at my "math", as getting the right master and cylinders ratios and size is a daunting task, at least for me. It was only by some trial and error, that in my case I arrived at a good set of brakes, at least for my car. We totally lucked out that that BMW caliper worked so well at the back. Talk about getting better lap times, but, that was also by just getting rid of those lousy drum brakes, and putting the cooling ducts on also.

[Derek]

This is sort of on topic, but here's something I noticed when I went lapping at Thunderhill in December. This was my first lapping day on my R compound V710s and my 280ZX/Porterfield R4-S setup got a soft pedal way quicker than in the past lapping days on my street tires (RT-615s). I should have expected that, but I guess the moral of the story is all things being equal the stickier the tires, the more work your brakes will be expected to do. Something else to consider!

[bertvorgon]

One tends to go in deeper, as the previous lap lets you realize..."wow...I stopped pretty good!" So, you carry more speed..and brake later.....which means more energy has to get dissapated as HEAT..and on it goes...till the next week link in the system crops up.

[Byron510]

I know of Mario's Brembo package, but I'm not rich. Those things are pretty huge though. What is the advantage to running such a large brake package?

Absolutely none if you don’t use them. They would be a hindrance and a waste of your hard earned money on a street car that occasionally sees a bit of weekend warrior work.

I did take Keith’s hand me down Dynalite calipers. It was an interim solution offered to me as I save for the Brakeman swap. I was modifying the strut/mount for it anyways and it just got a jump on the whole show – Thanks Keith, I’ve been quite happy with them from what I had been running. To know that it can get batter is inspiring!.

I’d previously run the 280ZX calipers on all my cars, but fading was still an issue as I hadn’t yet tried a competition pad – with the exception of once trying a set of metalmasters and scaring the s**I out of myself one day in the rain when I had to hit the bakes hard – fronts were stone cold, rears worked just fine – and around it came! Not a fun scenario, and one I don’t ever suggest! Needless to say I was a bit more careful when selecting pads for the Bronze. I run a Tilton parallel brake pedal set up with a balance bar with ¾” M/C’s so I can mechanically balance my braking front to rear – extremely effective and a mod that I would suggest to anyone with performance on their minds. I opted for the cockpit adjustable kit, and mounted the brake bias adjuster right beside my seat. I do adjust it in the rain as slippery roads do not give the same weight transfer characteristics, so I do need to dial in more rear brakes in the wet. The front pad I selected was the new Polymatrix A compound; Specialty Engineering’s advice. And it was sound. I do like them – A LOT!

My pedal box is pretty hi ratio. I was worries about being able to fit the box into the car. In retrospect, the standard length box would have been the better way to go, but hindsight is always 50/50. If I were to do it again, I think I would go with the long pedals. I have lost some feel, and have even considered dropping the M/C size down from ¾” to 5/8” just to try it. DON’T confuse this with a stock 510 set up. My pedal ratio is no where near the stock 510 set up, so don’t try to apply my M/C size to your plans – as was said earlier “All things being equal which they rarely are” – that’s a sound statement.

No complaints for the use I have with the car thus far. It’s yet to see the track, though. And I guess that will be the ultimate test – especially our local track which in known to be the brake eater track of the west coast.

Just my thoughts, just don’t over engineer your set up. Likely the simple solution (the 280ZX swap) is best for you. Then an upgraded pad then caliper if necessary.

Byron

[NasaRacing510]

strait from the Brakes for champions book

( Brakes dont stop a car, Tires do ! )

Brakes slow down the inerta of the wheels/tires that inturn slow down the car.

A properly balanced car ( Weight transfer and suspention set up ) affect the cars braking more than the pad choice or caliper size !

Hows your weight transfer??

Mines really heavy on the left side.....

[ktberube]

I run the Brakeman's 4 piston caliper and 10.5 rotor in a 13 inch wheel (3 piece Kodiaks). The calipers have a steel center (bridge) to help reduce flex at temperature. This adds a pound when compared to the junkwoods, but minimizes the flex. I stuck with the 13 inch wheels because of less unsprung, rotating weight and 13" tires are cheaper than 15s and come in a range of sizes and compounds.