1984 Chevy Camaro Z28 Big Brake Kits - Short Stoppin' Z
Improving A Third-Gen 1984 Chevy Camaro Z28's Braking-Without Installing A Whole New System
From the November, 2008 issue of Chevy High Performance
By John Nelson
Photography by John Nelson
Much as we're fans of big power, we're also fans of big braking performance. We think it only makes sense that a car's ability to go very fast should be matched by its ability to stop very quickly. Big brake kits are certainly an effective way to improve a musclecar's stopping ability, and they look really cool when peeking out from behind the large-diameter wheels it takes to accommodate them. But does it necessarily take big brakes-along with big wheels and tires-to achieve big braking performance? That's the question we wanted to answer in this experiment, in which we outfitted our '84 Z28 with braided stainless brake hoses from Classic Tube, brake pads from Hawk Performance, and high-performance front rotors from Power Slot. And as you'll see, there are significant gains to be had within the confines of a stock braking system.
Part one of our upgrade was to replace the stock rubber brake lines with StopFlex Stainless Steel Braided Hoses (DOT-certified) from Classic Tube. At its most basic, a brake system-whether manual or power, disc or drum-needs hydraulic pressure to work. More pressure generates more braking force, whether it's a caliper clamping onto a disc or a shoe pushing out against a drum. Rubber hoses, even when new, expand when subjected to this pressure, resulting in a spongy pedal and less braking force. StopFlex stainless lines don't expand, which translates to an increase in hose pressure and therefore more braking force. The firmer pedal feel that comes with the bargain also doesn't hurt when it comes to keeping things under control.
With that handled, we turned our attention toward the friction surfaces, starting with the rotors. We called on Power Slot for our front discs. The decidedly non-OEM slots, called Vac-U-Slots by Power Slot, improve braking performance by disposing of the heat, gases, and pad dust generated when the pads clamp down on the rotors. These waste products can actually become a barrier between the pad and rotor, inhibiting braking performance, so disposing of them is a key to maximizing stopping power.
And finally, we turned to what is arguably the most important part of a brake system, the brake pads. Stock-style, organic-composition pads are at best a compromise, as stopping power is sacrificed in favor of low price, low noise, and long wear. With this in mind, we sourced Hawk Performance for a set of its HPS (High Performance Street) pads. These pucks are intended for high-performance street cars, so we figured they were right up our alley. Their ferro carbon (Carbon Semi-Metallic) composition provides an extremely high coefficient of friction (stopping power), according to Hawk. This creates higher and more consistent torque values. In the real world, this translates into a more consistent pedal feel. These pads are also meant to handle the higher temperatures that come with repeated use without fading.
What we did
Upgraded the pads, rotors, and brake lines on an '84 Z28
For a relatively small investment, we got shorter and more consistent stopping performance
In a nutshell, braking power is like drivetrain power in one very important aspect-you have to have enough tire on your vehicle to transmit the forces of braking and acceleration to the ground. In that respect, modern, speed-rated, 17- and 18-inch rubber certainly has a great advantage. Many people, on the other hand, like a more traditional look-like what we have with the stock 15-inch five-spoke wheels on our Z28.
Hi-po 15-inch rubber isn't all that common these days, but we found a good alternative in Bridgestone's lineup with the Potenza G009. But in the time since we mounted these skins up, Bridgestone has redesigned them as the Potenza G019 Grid. Our Camaro's size-2 15/60R15-still comes H-rated. The tire line also includes several new V-rated 16- to 18-inch tires. Our H-rated versions are good for 130 mph, more than enough for this car for now. The two tires don't look all that different; the most noticeable visual difference is the new tires' Veri-Pitch tread design, meant to cut down on road noise, along with an advanced directional tread design to increase water evacuation (for those of you who actually drive in the wet). Other revisions have been made to improve grip in all phases of driving when compared to the older tire. We're quite satisfied with the G009s we've got mounted (at least until we can score 17-inchers), and anyone in search of good 15-inch rubber should consider the G019 Grid.
This was the starting point:...
This was the starting point: our '84 Z28's stock 10.5-inch rotors and Metric calipers, just like you'll find on the front of any F-body of the era, unless you were lucky enough to score a later 1LE car with its 12-inch rotors and PBR calipers. Obviously, the bigger rotors and upgraded calipers in such a setup will provide better braking performance. On the other hand, a few well-chosen improvements to the puny stock system can make it a stout performer in its own right.
We had a bit of an advantage...
We had a bit of an advantage when it came to extracting max braking performance from this Z28 since it came with factory rear disc brakes. The rotors measure the same as the fronts, 10.5 inches, and although the calipers are slightly different from the fronts, they take the same Hawk pads. Since a car's front brakes do most of the work, on the order of 70-80 percent, anything we get here is a bonus. That means if your car has rear drum brakes, there's still much to be gained by upgrading to Classic Tube's stainless braided hoses in the rear.
The third-gen Camaro's left...
The third-gen Camaro's left rear hose actually comes off the frame hardline and intersects the axle hardline, which runs right into the driver-side caliper. It requires some contortion to get at, much less photograph. Note right off the bat that we're using a line wrench on all the fittings to ensure that we don't round off any edges. The frame distribution block, which we've already disconnected, is just out of view.
So, what did it all get us? Testing was done with an Escort g-Timer GT2 Vehicle Performance Monitor we happened to have on hand, and with the stock brake setup in place, we registered a best stop of 156 feet, with a three-stop average slightly above that, which actually isn't bad. Pedal feel, however, was seriously lacking. The pedal was mushy; it was like you could feel the rubber hoses expanding as the pedal was mashed. Braking power was low at first, and increased as the pedal was depressed. And with repeated use, braking got predictably worse as temperatures increased.
It was notably different with the upgraded components in place. After bedding in the pads to the rotors as specified by Hawk, several things quickly became evident. Right off the bat, we had a much firmer pedal to deal with-no more mushy pedal feel. Consequently, brake response was immediate, though not grabby. Braking power was more consistent throughout the pedal's travel-and there was more of it. We recorded a best stop of 142 feet, a very good improvement over our original 156-foot figure. In a panic-stop situation, 14 feet could be enough to save your car.
Just as important, our three-stop average was 9 feet better, and we think it can get even better as we adjust to the more positive feel of the new brakes. In fact, we spent at least an hour beating on our Z in search of the perfect stop, and the brakes never really faded. Unlike the stockers, which registered 170-plus feet as testing wore on, the new setup stayed firmly in the 150s for as long as we cared to abuse it-and this on a day that was at least 10 degrees hotter.
So in the end, while we're still craving a set of 17s and the platters to fill them, it turned out that our merely stock system was actually quite capable when properly outfitted. And while third-gen Camaros are noted for handling platforms that should be able to stop well, here's the cool thing: The principles we applied here apply to any Chevy that's still wearing its stock brakes. Increase the line pressure and upgrade the friction surfaces, and as long as you've got decent tires in place, you'll get better braking. You'll appreciate it when you really need to stop-and it doesn't cost all that much, especially if you're already due for a brake job.
The right rear Camaro brake...
The right rear Camaro brake is set up a bit differently, as the hardline from the distribution block runs out along the axle, where it connects with a hose that connects to the front-mounted passenger-side caliper. As you can see, we've already removed the parking brake spring and are working on the bracket so we can get at the lower caliper pin. We won't keep you in suspense here-regardless of what the book says, the easiest way to get this pin out is to drop the lower control arm.
We don't intend to cover every...
We don't intend to cover every single detail involved in this brake upgrade-if you've done a brake job, you can do this. We will, on the other hand, try to impart some useful details. For starters, we're sure you can get the front rotors off, and we'll discuss the bearings and seals later. At this point, we removed the caliper banjo bolt with the appropriate flare wrench. It makes an unavoidable mess, so you may want to put a pan underneath.
At the frame fitting-and this...
At the frame fitting-and this goes for installing the new hoses as well as removing the old-you'll first need to remove the H-clip, then hold the flexline fitting in place with a flare wrench as you loosen the frameline fitting. Again, unless you've let the system run dry before beginning (not recommended, as it will take a long time to get the air out of the lines), the result is a mess, so plan accordingly.
We chose Classic Tube's StopFlex...
We chose Classic Tube's StopFlex SS DOT braided hose kit for '82-84 four-wheel disc Camaros to upgrade our ride. These hoses have a four-layer design that starts with a Teflon PTFE core, followed by a Kevlar core, an elastomer barrier, and then the outer stainless steel braid (which is finished with a clear coat of vinyl). The bottom line is that they're DOT-approved for use on the street, they have no volumetric expansion, and they're corrosion-resistant to boot. Kits are for just about any disc/disc or disc/drum combo found on third-gen Camaros, as well as a multitude of other Chevy models.
There are really only a few...
There are really only a few things to remember when installing braided hoses. The most important is to use new crush washers (included in the StopFlex kit) where indicated whenever changing lines, one on each side of the banjo fitting.
On the other end, it's simply...
On the other end, it's simply a matter of placing the new hose through the frame fitting, then linking it up with the frameline. After we tightened everything down (using a flare wrench, of course), we clipped it back with one of the new H-clips included in the hose kit. The new hose should roughly follow the path of the original hose.
This is something to take...
This is something to take note of: These hoses are constructed using a seat-to-seat seal at the juncture of the hose and the end fitting. The hose end can actually be unscrewed from the hose itself if need be; this could be an advantage during installation. In any case, once the hose is installed and routed, these areas must be tightened, checked for leaks, then tightened again if necessary. How tight is tight enough? Once the seat-to-seat seal has been achieved and you've got no leakage, you're good to go. Be sure to recheck this undercar-started, power-boosted pressure.
We decided on Power Slot rotors...
We decided on Power Slot rotors to continue the upgrade of our subject Camaro's front binders. These premium replacement rotors match OEM specs for plate thickness, cooling vane design, and number of cooling vanes. Although they measure the same small 10.5-inch diameter as the factory pieces, the Vac-U-Slot's design allows the heat and gases caused by the act of pad meeting rotor to be evacuated, which improves stopping power, reduces fade, and even helps keep the pad surface clean. The Vac-U-Slot also serves as a wear indicator-when you can't see the slot at the outside edge of the rotor, it's time for a replacement.
Though there are ways to improvise,...
Though there are ways to improvise, we used a seal puller to remove the front rotor dust seals, then extracted the bearings. After thoroughly cleaning the bearings and ensuring that they were still serviceable, we regreased them and transplanted them into new rotors. Always be sure to use a new dust seal. Seating them with a seal installer makes for a proper-and easier-installation.
For our brake pads, we chose...
For our brake pads, we chose Hawk Performance's HPS (High Performance Street) series pads. HPS pads are intended for high-performance street use, which is perfect for what we have in mind for this Z28. Looking for something more aggressive? Because the GM Metric caliper is the spec caliper in many circle track series, pads are also available in the HP Plus, which work well on the street or track, all the way up to full race compounds, the DTC versions being the top of the hill. It all depends on how aggressively you want to stop, how much noise you can tolerate, and how long you want your pads to last.
Skipping ahead a bit here,...
Skipping ahead a bit here, we've installed our new rotors up front, and loaded the calipers up with the new pads, after coating the rears of the pads with antisqueal compound. Here's another tip for smooth brake operation: Notice that we've removed the corrosion on our caliper pins with a wire wheel and treated the threads with antiseize.
With the caliper in place...
With the caliper in place as we tightened the caliper pins, it's easy to see the proper routing of the new stainless brakes hoses from the back side. Ideally, the hoses should follow the stock hoses' path as closely as possible, and they shouldn't rub against any other surfaces, whether flat or smooth. After this photo was taken, we went back and changed the lower ball joint cotter pin placement, just to eliminate any possible interference.
Here's a tip on the driver-side...
Here's a tip on the driver-side rear frameline. The hardlines on either side of the T-fitting will need to be bent slightly to line up with the new hose. It's much easier to mount the two hardlines to the T-fitting and then reattach the fitting to the rear axlehousing. There's less risk of tweaking the hardline that way.
All that's left then is to...
All that's left then is to attach the other end of the new stainless hose to the frame fitting, tighten it into place, and reattach the upper end to the frame mount with one of the new H-clips included in the Classic Tube kit.
Removing the caliper on the...
Removing the caliper on the passenger side is a headache, but the hose swap is a simple R&R affair. Don't forget to tighten the hose end to hose junctures (arrows) to ensure the factory seat-to-seat seal is leak-free.
The right rear disc was actually...
The right rear disc was actually rusted to the axle flange. Once we excised it, we took a wire wheel to the flange, then coated the whole thing with antiseize before installing a set of OEM-replacement Centric rear rotors as a matter of maintenance. Also note that we cleaned up the caliper surfaces that the pad slides along and gave it a coat of antiseize as well (arrow).
Once we had thoroughly bled...
Once we had thoroughly bled the brake system, we took the car out and bedded in the pads and rotors. First, the vehicle must be driven 10-20 miles of "normal" braking to wear away the corrosion-resistant silver cadmium plating from the contact area. Hawk then recommends performing 6 to 10 stops from 30-35 mph, followed by another 2 to 3 stops from 40-45 mph, which applies a layer of pad material onto the rotor surface. This transfer film creates adhesive friction, meaning the pad and rotor adhere to each other during stopping. This layer also acts as a buffer between the pad and rotor. Response, wear, and consistency are all improved-and we can testify to that.
Although we can't match the...
Although we can't match the looks of a big set of four-piston calipers with our factory squeezers, we decided to dress up our upgraded stockers anyway with a Brake Caliper PaintSystem Set. The kit comes with a cleaning spray, self-leveling paint (basic black for us), a reactor, a stir stick, and an application brush. We also picked up wire brushes to aid our caliper prep, and Eastwood recommended we wear a respirator for the job. The calipers don't have to be off the car to do this, so we cleaned them thoroughly, masked them off, mixed the paint as indicated, and went to work. There's enough here to put three coats on four calipers. Two coats worked for us, and as you can see in our lead photo, our improved stopping power now comes with improved looks.
|PARTS LIST |
|ITEM ||PRICE |
|Power Slot left front rotor ||$101 |
|Power Slot right front rotor ||101 |
|Stop Flex brake hose kit ||145 |
|Rear rotors (2) ||80 |
|Hawk HPS pads (2 sets) ||102 |
|Caliper painting kit ||40 |
|Respirator ||50 |
|Wire brushes (3) ||9 |
|Total ||$628 |
|BRAKING IT DOWN |
| ||Best ||3-Stop Avg. |
|Stock ||156 ft ||158 ft |
|Enhanced ||142 ft ||147 ft |
|Bridgestone Firestone North American Tire|
|Power Slot/Centric Parts|