When the fourth-generation Camaro and Firebird were introduced in 1993, it was heralded as the best F-body yet. With 27 hp on tap, a 6-speed manual transmission, fighter-jet styling, razor-sharp rack and pinion steering, true double A-arm suspension up front and standard 16-inch alloy wheels wrapped with Goodyear's best Gatorbacks, you could really haul the mail. It didn't cost a lot either, with the base price for an LT1-equipped Z28 or Firebird Formula going out the door for well under $18K in the early years.
But there was trouble in paradise. V8-powered F-bodies had marginal 10.9-inch diameter rotors up front, and they were clamped by over-worked single-piston calipers made of cast iron. It wasn't until the LS1-powered cars were introduced in 1998 that GM wised up and increased the front brake rotor diameter to 12 inches. On those earlier LT1 cars, however, you could find yourself in trouble really quick if you had to slow down in a hurry from a buck twenty!
Triple-digit speeds are certainly nothing new to our 1994 Camaro Z28 test car. We've made numerous trips to the track over the years and always lamented at how poorly it stopped. The gripping power of the brakes (or lack thereof) was only overshadowed by the nonexistent grip of the rock-hard no-name tires we were using. We quickly solved that problem with a change over to Nitto NT555 RII Road Race Extreme tires (275/40ZR17). Our stopping distance from 60 mph plunged from 144 feet to just 111 feet with nothing more than a rim/tire change! We've gotta give those Nitto R-compounds some serious praise here, because the best brakes in the world won't work without great tires to grab the pavement.
The down side to our newfound stopping prowess was that we could only do it once before the fade set in. The second, third and fourth tries resulted in successively longer stopping distances, boiling the brake fluid and making some really funky clouds of brake smoke which wafted from the stock calipers. Not good.
Meanwhile, we had been watching the folks from Stainless Steel Brakes Corporation with interest. They had just released their new line of Tri-Power Force 10 calipers for the C5 Corvette, and we knew from experience that C5 brake parts adapted very well to fourth-gen F-bodies. Sure enough, a few months later, we got a press release from SSBC introducing their Tri-Power kit for F-bodies.In fourth-gen F-body trim, the Tri-Power system (part No. A123-15, $1,995) lays the smack down on the stock brakes big time. Large 12.75-inch diameter vented rotors offer enough leverage and surface area to slow these heavy cars down without breaking a sweat. Braided stainless steel brake lines also reduce sponginess in the pedal because they don't expand under pressure like the stock rubber hoses. New spindles make the installation easier with no pieces needing to be cut with a Sawzall like other kits on the market.
But the best part of the system is the new three-piston Tri-Power caliper. Three pistons do a much better job than one piston for one simple reason: clamping force is evenly distributed across the pad surface, and that makes a given pad area more effective. The caliper itself is made of aircraft-quality billet aluminum for weight reduction and strength, but each of the three 38mm pistons is made of corrosion-resistant stainless steel. This minimizes heat transfer from the pad to the fluid resulting in zero brake fade. And since this is a system designed for street cars, the Tri-Power caliper incorporates dust seals to keep trash out of the clean bits. Coupled to the larger 12.75-inch vented rotor, this beefy three-piston floating caliper makes short work out of stopping and looks good while doing it. Speaking of looking good, for a small additional cost, SSBC can powdercoat your Tri-Power calipers red, black or yellow.
Rounding out the kit are some trick steel mounting brackets. These solid pieces are the bridge from the Tri-Power caliper to the new spindle. Bolts, washers, banjo fittings, brake lines, calipers, rotors, spindles, brackets, pads--it's all there. Just supply the tools and some high-quality brake fluid. (We suggest Ford DOT 3 fluid, which is one of the few that still comes sealed in a steel can.)
We performed the Tri-Power installation in the Primedia Tech Center with technician Jason Scudellari turning the wrenches. (Yes, those are his flamboyant tattoos in the photos!) Even with the occasional snafu, the entire swap was over in less than five hours.
We also took the liberty of weighing the stock pieces against the new SSBC pieces. To make things fair, we weighed the stock caliper, pads, rotor and spindle against the Tri-Power's caliper, pads, rotor, spindle and mounting bracket. Leaving out the ABS sensor (which is reused), we found the Tri-Power kit to weigh 47 pounds (one side only) versus the stock brake's 46.5 lbs. While SSBC claims the Tri-Power brakes are lighter than stock, we interpret this to mean the caliper only, which is correct. We also want to note that stopping ability is also a function of the brakes' ability to absorb heat--and more mass in the right place makes that easier. From an engineering standpoint, the weight savings of the Tri-Power caliper is offset by the extra beefcake in the rotor, which is a smart trade-off. Remember, the stock rotor is only 10.9 inches and the stock caliper is a cast-iron single-piston boat anchor! We don't mind the Tri-Power's extra pound of unsprung weight because it's in an area that really pays off.
After the initial pad break-in period, we were pleased with the Tri-Power's stopping ability in regular driving. Even panic stops provided excellent performance. However, we noticed that under extremely hard braking we weren't able to invoke the ABS at all and braking distance was noticeably longer. At first suspecting the coating on the rotors and the green pads, we waited a month until these could be ruled out as suspects. Our master cylinder was also cleared of any wrongdoing because pedal travel was the same as before and the pedal never bottomed out (an indication of a worn master cylinder or one which has too little volume).
Finally, it dawned on us that we had in the intervening period installed our Edelbrock Performer LT1 heads and cam. (See "The Equalizer," December 2004.) Our engine vacuum had taken a nosedive from 18 inches to 11 inches, and that isn't enough to get the job done on any kind of vacuum-assisted brake system! The solution is for us to install a milder cam, such as the ACCEL 74211, or to use SSBC's vacuum pump kit (part No. 28146, $265). Due to the smog laws in California and our upcoming date with governor Schwarzenegger's dreaded dyno, we'll probably yank the cam to get back our engine vacuum.
We put in a call to SSBC's tech department and they verified our problem was indeed due to low engine vacuum. They also added that engine vacuum needs to be at least 18 inches for their Tri-Power system to work at its maximum potential. Problem solved.
This is a great lesson for those of you considering any kind of brake upgrade--especially on cars with bigger cams. Good brake performance relies on a strong vacuum signal. If you don't want to live with an auxiliary electrical vacuum pump, there is the other option of converting to a mechanical, non-boosted system. This requires a higher pedal ratio (the rod on the brake lever needs to be moved up toward the pivot) and a new mechanical master cylinder such as that made by Tilton. Another alternative is a hydro-boost system which uses pressure from the power steering pump to multiply brake pedal input. These are most commonly employed on turbocharged cars that see little or no vacuum on decel. For more info on that, check out No Limit Engineering at www.nolimit.net (888-297-6032). A hydro-boost system typically generates 20 percent more line pressure than an 8-inch vacuum booster and is unaffected by low vacuum conditions.
With more vacuum, we know the braking performance on our Tri-Power system would be earth-shaking. We found no fault whatsoever in the SSBC kit and have no problem making the Tri-Power a strong recommendation for those cars needing the ultimate in fourth-generation F-body brakes. We will have to wait, however, to fully realize that performance ourselves. As we go to press, we've also learned that SSBC plans on offering the Tri-Power kit for mid- and full-sized GM cars, trucks, and late-model Mustangs. Now everybody will be able to get in on the Tri-Power stopping action.
vehicle lift or jack and jackstands
ball joint & tie rod cotter pins (6)
12x40mm, 1.75 pitch hardened Allen bolts (4)
9/16, 7/16 & 15/16-inch box wrenches
1/2 & 9/16-inch sockets
8mm, 15mm & 18mm box wrenches
12mm tubing wrench
3/8-inch Allen wrench
10mm Allen wrench
Fresh can of high-performance brake fluid