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Baer Claw Kit Install on a 1999 Chevy Tahoe - Braking the Girl
The Three Ingredients For Good Stopping
From the June, 2009 issue of Sport Truck
By Rick Amado
Photography by Rick Amado
 Todd Gartshore actually got...  Todd Gartshore actually got us started by taking the Tahoe out for some before testing. He used his windshield-mounted Stalker radar gun, which is linked to his laptop computer. He did three stops each from 60 mph and 90 mph, and he saved the data on the laptop for later retrieval. One of the methods that Gartshore employed was doing back-to-back panic stops. This means that he applied the brakes to the point of almost locking up the wheels and stays on the pedal until the vehicle came to a complete stop. He repeated the procedure without giving the brakes time to cool. This method ended up heating the factory brake pads to the point that they were billowing smoke and exhibiting excessive brake-fade.  After returning to the shop,...  After returning to the shop, safely securing the Tahoe on the hoist, and removing the wheels and brake drums, Dutch removed the differential cover and drained the gear oil from the rearend so that he could remove the axles. The Baer Claw kit converts the rear drum brakes to disc, and the axles must be pulled before the backing plates can be removed from the truck.  With the cover removed and...  With the cover removed and the oil drained, Dutch removed the retaining bolt and lock pin that secures the axles in the rear-end housing.  Dutch pushed the axles in...  Dutch pushed the axles in slightly and removed the retaining clip, thus freeing the axles from the ring-and-pinion.  Dutch removed the axles from...  Dutch removed the axles from the housing and carefully set them aside. Its important not to bang the axles around since damaged splines dont like to be reinstalled.  Dutch removed the brake line...  Dutch removed the brake line from the back of the wheel cylinder and plugged it with the handy plugs that Baer Racing includes in its Baer Claw kit. The plug minimizes brake fluid loss, reducing fluid consumption during the bleeding that will take place after the install.  With the axles out, Dutch...  With the axles out, Dutch removed the four bolts that secure the brake backing plate to the axlehousing. He left the parking brake cables attached and let the backing plates dangle from them. The leading ends of the parking brake cables seem to be the most confusing part of this swap for the home mechanic, so Dutch recommends that you leave them alone until you are ready to accomplish that step.  Once the old brakes were liberated...  Once the old brakes were liberated from the axlehousing, Dutch installed the caliper mounting plate using the four holes that held the factory backing plates in place. The plates are mirror images of each other and can be mounted with the calipers ahead of or behind the axle centerline, as long as the calipers bleeder valve is at the highest point in relation to the piston.  When converting the rear to...  When converting the rear to disc, its important to check the diameter of the axle flange. The outside diameter (pointer) needs to be 6.55 inches maximum for proper rotor clearance. If the diameter is larger than 6.55, the rotor will not seat properly and the flange will need to be turned down on an axle lathe. Any competent machine shop should be able to handle this procedure with ease. We lucked out, as our axle flange measured 6.54 inches.  With the mounting plates secure,...  With the mounting plates secure, Dutch reinstalled the axleshafts and secured them by reversing the removal procedure. He applied some silicone gasket material to the sealing surface on the cover, reinstalled it, and refilled the differential with the proper lubricant.  Once the axles were secure,...  Once the axles were secure, Dutch installed the new rotors and held them in position with a couple of lug nuts.  He installed the PBR calipers...  He installed the PBR calipers with the hardware provided and checked for proper alignment between the caliper and the rotor. The rotor should be centered within the caliper.  Baer added a hardline bracket...  Baer added a hardline bracket to the axlehousing to secure the hardline where it joins the braided line. Since the calipers float, a flexible line is required to avoid fatigue in the hardline. This prevents the possibility of brake line failure. The bracket needs only to be aligned so that it doesnt interfere with any moving parts under the truck. After securing the bracket with the hose clamp, he bent the hardline around 90 degrees so that it fit into the hole in the bracket, being careful not to kink or damage the line.  With the caliper secure on...  With the caliper secure on the mounting bracket, Dutch added a ballast to the rear of the caliper. The ballast dampens vibration and helps the brakes operate quietly.  Here is the completed installation...  Here is the completed installation of the rear disc kit with the flex line installed. The kit uses a banjo fitting at the caliper and stainless braided line for maximum performance.  Dutch installed the park brake...  Dutch installed the park brake cables next. He started with the caliper end. He slid the end through the bracket and secured it with a C-clip. He then routed the new cable along where the factory cable was. He repeated this operation on the passenger side as well, routing both cables to the driver-side framerail.  Its important to know...  Its important to know that the forward ends of the park cables are different from each other. They need to be placed on their respective sides of the truck, or the park brake isnt going to operate properly. This is why Dutch left them for last. He simply followed the cables and installed the new ones exactly as the factory cables were installed. This is the driver-side cable with its adjustable end. (The cable from the passenger side has no adjustment.) Behind it, you can see the passenger-side cable as it travels forward to the other end of the bracket.  With the rear brakes completed,...  With the rear brakes completed, Dutch moved to the front of the Tahoe. He removed the tie rod ends and ball joints by loosening the nuts and tapping the spindle with a hammer to release the tapers. After removing the brake line and speed sensor wire from the caliper, he removed the entire spindle complete with the rotor and caliper intact. The new front brakes bolt on as a complete spindle, rotor, and caliper assembly.  Baer Racings new spindle...  Baer Racings new spindle assembly is slightly narrower than the factory unit. It rides a bit further inboard than the factory piece. This allows Baer to use thicker (more mass for better performance) rotors and still retain the proper track width in the front end. The lower control arm must be massaged with a sledge to allow the rotor more clearance. The lip on the lower edge of the control arm needed to be rolled under a bit for proper fit.  Test fitting during this phase...  Test fitting during this phase is critical. The control arm must be modified around the perimeter of the ball joint to allow clearance in a turning situation as well. The spindle assembly was test-fit and turned back and forth to simulate steering to verify that the rotor had proper clearance. One quarter inch is acceptable. Once adequate clearance was attained, the spindle was secured with its proper hardware and a new stainless braided brake line was installed in place of the factory rubber line. The front rotors in the Baer Claw kit are 2 inches larger than the factory rotor, and the calipers boast twin pistons for improved braking performance.  With the under-truck phase...  With the under-truck phase complete, Dutch crawled under the hood to change the master cylinder. He changed the master from a 1 1/8-inch bore to a 1-inch bore. Since the new front calipers have two smaller pistons as opposed to one larger one (factory), they require higher line pressure with less fluid volume, and the switch to a smaller diameter master cylinder provides just that.  With the brake system installation...  With the brake system installation complete and the new master cylinder filled with fresh fluid, Hal Baer applies a vacuum brake bleeder to the front calipers to draw fluid from the master to the calipers. He repeated this step on the other side only to fill the lines up with fluid, thus making the bleeding easier.  If youve ever bled brakes,...  If youve ever bled brakes, you know how this conversation goes. The guy in the cab pumps up the brakes, holds the pedal down, and yells OK! Then the guy under the truck opens the bleeder valve, lets it bleed, closes it, and yells OK! Then the process (OK) is repeated until no more air (OK) comes out of the lines. Hal Baer repeated this procedure on all four corners until he was satisfied that all of the lines were free of air bubbles. After the wheels were reinstalled and the truck was safely back on earth, it was time for the real test. Lets hit the street! n  The numbers. Its all about the go, brountil that lawn mower-handled, huge-stickered, 6-inch-exhaust-tip-on-a-1-inch-pipe, rice-burning skateboard pulls out in front of you in a feeble attempt to show you just how fast four cylinders really arent. Then its time for some whoa, and if youre not prepared, there goes your billet grille, cowl hood, fenders, and probably a wheel or two. It seems that the one thing that gets overlooked the most when modifying a truck just happens to be the one thing that can save all of that custom work in a panic stop situation. Thats right, were talking about brakes. We contacted Todd Gartshore at Baer Racing in Phoenix and he told us that they had a Baer Claw kit. Founded in 1986 by Hal Baer, Baer Racing started out as a racing team that competed and won in various professional road racing series as well as several amateur classes. The business originally provided race preparation to racers and hardcore enthusiasts. This included building rollcages, suspensions, and even complete racecars. Baer Racing eventually realized that most of the passing in races occurred during braking, so the company set out to learn as much about braking systems as it could. With the newfound knowledge applied to the cars it built, Baer-equipped cars began beating out teams that were substantially better funded. This created a demand for Baer Racing brake expertise from which Baer Claw brake systems were born. Once it was entirely focused on brakes, Baer Racing was then able to concentrate its efforts on design, testing, and improving its braking systems for the ultimate in stopping power. As the business grew along with Baer Racings reputation, the company began designing and building custom braking systems for special projects being built by various OE manufacturers, and eventually became a supplier of systems and components for OEMs such as ASC-McLaren, GM, Ford, Roush, and Shelby. Today, Baer Racing is one of the leading manufacturers of aftermarket braking systems and its reputation speaks for itself. One of the major misconceptions about brakes is that the easier it is to lock up the wheels, the better the brakes are. This is far from the truth. A locked wheel uses the tires adhesion properties to stop the vehicle, instead of the brakes ability to turn momentum into heat. When brakes are applied, the forward momentum of the vehicle is converted into heat through the friction between the pad and the rotor. Since heat is a brakes natural enemy, the brakes ability to absorb and dissipate heat is what really gives the brakes better performance. Baer Racing achieves superior brake performance in its systems through the use of the three ingredients needed for good stopping. The first is caliper stability. The mounting of the caliper and the rigidity of the caliper body itself are important to provide solid clamping forces of the brake pad to the rotor. Next comes capability of the rotor. Two factors enter into this. The diameter of the rotor is important because a larger rotor gives the brakes greater leverage and thus increased stopping power. The other factor is rotor mass. The rotor must be able to absorb and dissipate heat for proper brake performance, so its natural that a rotor with increased mass is more capable of absorbing and storing energy. The third ingredient is good friction material. Gartshore says, Pads are truly the wild card in ultimate brake performance. Baer indicates that an optimum pad for performance street use must be a balance of excellent levels of initial friction (when you first tip into the pedal), good to high maximum friction (the greatest torque which can be generated in a panic stop), good progression (how easy it is to modulate friction levels with the brake pedal), and resistance to temperature-related fade. All must be accomplished with a minimum of noise and dusta balance that Baer believes is substantially harder than finding the right race-only pad. Baer Racing strives for a balance between these three factors and this is what gives the company its edge. Baer Racing uses both PBR and Alcon calipers for its kits. PBR is an Australian company that supplies many high volume OE applications. PBR calipers have quickly become an industry standard for high-performance brake calipers, and the companys combination of design, performance, and durability is tough to beat for the price. In fact, GM uses PBR calipers extensively for OE applications. Baer Racing is also the exclusive U.S. source for Alcon road-going calipers. These high-performance multi-piston calipers are actually built by the same technicians that build Alcons racing calipers. In fact, Baer uses Alcon racing calipers that have been fitted with proper dust and weather seals for better performance during the rigors of daily driving. Out in the shop, we had Dutch, one of Baer Racings expert technicians, show us the proper way to install a Baer Claw kit onto a 99 Tahoe.
Baer Racing Inc.
3108 W. Thomas Rd.
Ste. 1201
Phoenix
AZ
85017
www.baer.com
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