|
|
1976 Chevrolet Camaro - Project g-28 Braking News
PHR's new project car gets binders from Baer, and another good report card from the test track.
January, 2009
By Johnny Hunkins
Photography by Johnny Hunkins, Nick Licata
Project g/28, our Second-Generation '76 Camaro, takes yet another big bite out of our performance goals this month--this time in the area of stopping power. For part three of our series, we drove out to Baer Racing in Phoenix, Arizona, to get an upgraded front disc brake system and a rear-disc conversion. But before we get into the details, first some background. Our goals for this project are to build a practical and affordable g-Machine that can knock down 0.90g on the 200ft skidpad, run the 420ft slalom cones better than 46 mph, stop from 60 mph in 120 feet or less and run the quarter mile in the high 12s. Those are pretty lofty goals, but the toughest goal is the budget: do all this--price of the car included--for under $20,000. So far, we've spent $6,189. That bought us our project car for $2,300, our PST suspension, Global West upper control arms, Weld wheels and Falken FK-451 tires. So far, we've improved our skidpad road holding from 0.70g to 0.79g, our slalom speed from 40.3 mph to 46.2 mph and our 60-0 mph braking distance from 216.9 feet to 134.1 feet. We haven't touched anything in the engine compartment or driveline yet, so our quarter-mile performance remains at a snail-like 17.63 seconds at 78.6 mph. (Check out the sidebar "Charting The Changes." If you missed parts 1 and 2, you can also check out the parts list sidebar to see an itemized list of the hardware.) Our Baer brakes cost a total of $2,275; that breaks down into the GT front disc system for $1,345, the rear Sport system for $875 and an adjustable proportioning valve for $55. We also want to point out that the total outlay for the complete brake package on project g/28 is significantly less than equivalent performing kits from other sources. We can now use the money we saved in some other area down the line, because there's always an unexpected expense somewhere. Braking is often overlooked in the hot rodding world, often being forsaken for more glamorous hardware in the powertrain. But the need for better brakes is even more acute when the power goes up because the car is capable of even greater speed. Baer also knows that brake hardware is an afterthought for many people, so they build the bulk of their kits with off-the-shelf hardware from OEM manufacturer PBR. This brings the cost down significantly because the OEMs have already paid for the R&D and volume manufacturing. In the case of our GT front system, the dual-piston pin-drive caliper from the Z51 C5 Corvette is used. In the rear Sport system, the single-piston PBR caliper from the C4 Corvette and Fourth-Generation Camaro/Firebird is used, once again maximizing our dollar in the areas of performance, reliability and serviceability. Braking performance is based on two factors: the amount of torque you can apply to the rotor, and the amount of traction available at the tire's contact patch. Even before we added our Baer brakes, we discovered that we could improve our stopping distance just by increasing our tire contact patch; with the factory rolling stock we stopped in 216.9 feet and with the 18-inch Falken tires, we chopped that down to 163.9 feet, an improvement of 53 feet (24 percent). With the Baer brakes, 60-0 stopping distance improved to 134.1 feet, for a total duction of 82 feet (38 percent). The improvement was well worth the effort, but we still aren't at our goal of stopping in 120 feet or less. We're once again at the limit of adhesion with our tires; no amount of extra brake torque is going to stop the car quicker. What we need for that extra 14 feet is a stickier R-compound DOT tire, which we've found in the Nitto NT555-RII. We'll be trying some 275/40R17s, which will require some different rims than the 18-inch Welds we have now. The Nitto tire will provide a wider footprint (a 275 cross section instead of our current 255 cross section) and more adhesion via a softer rubber compound. The change in rubber will graphically illustrate the impact R-compound tires have on overall performance; braking distance, slalom speed and skidpad performance will all improve dramatically. The question is, how much? Stay tuned! 
|  Baer's GT brake system for...  Baer's GT brake system for Second-Generation Camaros and Firebirds ('70-'81) cost us $1,345 (part No. 1301057). The kit includes 12.75-inch vented one-piece rotors, PBR two-piston pin-drive calipers, caliper brackets, new spindles, PBR street pads, stainless steel brake hoses, a new master cylinder and all the hardware necessary for a complete assembly. Over the years, we've come to rely on the fact that Baer's kits are complete and easy to install, and this one is no different. In fact, our kit came pre-assembled (spindle, caliper brackets, wheel bearings, caliper and rotor). |  The PBR two-piston pin-drive...  The PBR two-piston pin-drive caliper in the Baer GT kit was originally developed for the Z51 C5 Corvette, which has proven itself on the street and on the track over the last nine years. This isn't our first encounter with this caliper--we've used it on a '93 Firebird Formula and a '94 Corvette, which were both road raced. We especially like how many choices there are for street and race pads (since it's a factory Corvette part). |  The GT kit for Second-Generation...  The GT kit for Second-Generation Camaros and Firebirds includes this smaller-diameter 15/16-inch bore master cylinder. This is hydraulically matched to the higher pressure needs of the PBR caliper. Since our pushrod was shorter, we used the included pushrod spacer (Baer calls this a "bullet" due to its shape) included with the kit. |  Baer's Sport system (part...  Baer's Sport system (part No. 1302041, $875) is designed to convert drum brakes to disc brakes on '75-'81 Camaros and Firebirds. It comes with everything you'll need (rotors, single-piston PBR calipers, braided stainless steel brake hoses, parking brake cables, pads, mounting brackets and mounting hardware). If you plan on racing like us, you'll also want to purchase the adjustable proportioning valve for $55. |  To upgrade the rear brakes,...  To upgrade the rear brakes, you'll have to pull the rear axles. We took that opportunity to see what was loaded in the rear diff. We found 2.73 gears (41 ring teeth and 15 pinion teeth) and an open rear end. This would've been an ideal time to swap to a three-series gear and a Truetrac differential from Detroit Locker, but we didn't think that far ahead. One thing we'd like to point out is that the 8.5-inch rear in Second-Generation Camaros is plenty strong enough to road race. The 8.5-inch rear has been used in Turbo Buicks for years and at the drag strip is a solid performing piece down to the high 10s. Stronger axles do help, but the 8.5-inch rear is worth keeping. |  Installing the Baer Sport...  Installing the Baer Sport kit is a simple affair. Just attach the Baer caliper bracket to the axle, slide the axle back in, slip on the rotor, bolt the caliper to the bracket, and check the clearance between the caliper anchor and the rotor (0.030-inch clearance is required to prevent excessive wear). Here, Baer technician "Dutch" Miller is tightening the caliper to the caliper bracket. The next step is attaching the parking brake cable and hydraulic line. |  Baer also makes wheel spacers,...  Baer also makes wheel spacers, so we tried these quarter-inch thick pieces to get the rear wheels out a little more. It helped the stance and clearance some, but our Weld wheels really need far less back spacing than a spacer can provide. |  Up front, the Baer GT system...  Up front, the Baer GT system is already assembled so just pull the stock spindle/brake assemblies and drop the Baer pieces on. You'll need a new alignment due to slight differences from production tolerance, but it's a true bolt-on affair. Note the Heidt's/QA1 coil-over suspension--which was installed at the time for a test in sister magazine Super Chevy. We'll be changing back to our original PST/Global West system before final track testing is complete. |  The Baer GT front rotor is...  The Baer GT front rotor is 12.75 inches in diameter and is 1.25 inches thick. This is the kind of beefcake we need to stop our 3,600lb Camaro on a road course! Customers can also elect to step up to the GT-Plus system, which has a two-piece rotor with an aluminum hat. The GT-Plus rotor is 13 inches in diameter, but is lighter in weight due to the alloy hat. |  Baer technician "Dutch" Miller...  Baer technician "Dutch" Miller has installed the new master cylinder along with a new rear proportioning valve (lower right). The adjustable prop valve reduces line pressure to the rear Sport disc brake system by turning the dial. Later on at the test track, we would make a series of adjustments to this valve to delay lock-up of the rear brakes. Please note that due to weight balance, suspension and tire type, all cars will find a different ideal bias between the front and rear brakes. |
Discuss in our Forums
Ford Mustang Research
Get updated on all your car buying needs from safety features, to specs, to crash test ratings and options. Get all the information you need if you are interested in buying a new car like the Ford Mustang. The 2011 Mustang is available with the following engine options: V8, V6, and comes with comparable warranty coverage to other vehicles in its class. Also check out the Dodge Charger and the Chevy Corvette
|
|