Since a few people have inquired about these mysterious SLH brake upgrade packages. I have decided to reprint all the info I have to the net; thus anyone can learn about them. It should be noted that this information as it will be presented is geared toward L-bodies, ie the Charger/Omni/Rampage platform. PLEASE NOTE that the Rampage/Scamps have some unique hardware which raises some special concerns; you ought to do some additional research before wrenching on one of the little trucks. Also, this info may apply to other Chrysler FWD cars (such as the Daytona, etc) depending on what brakes they are equipped with from the factory--you'll have to examine your own car and make your own judgement call.
Also, I will give credit where it is due: these articles were written by Mark Panos, a local Shelby club member. These articles appeared in our monthly club newsletter; the newsletter dates are given for those who may have access to them.
Finally, please note that I have merely typed in the info as it appeared except for some grammatical changes; these were made solely to clarify and/or simplify the material. I provide this information as-is with no expressed or implied guarantee whatsoever. Further, I assume NO LIABILITY for what you do with this information; if you are not competent to repair your own braking system then hire someone who is.
In the continuing quest to upgrade the 83-84 Shelby Charger and the 84 Omni GLH, let's not forget about stopping power. The normally aspirated cars were equipped with 200mm diameter rear drum brakes. Hardly adequate for stock, much less for a performance car.
The logical upgrade is to locate a Daytona or a similar car in a wrecking yard with 220mm drums. Purchase the drum and hub assembly and the brake backing plate. Next, go to a local parts store and purchase new wheel cylinders and some premium grade brake shoes. Also have the drums refinished and specify that the finish cut be performed at the machine's slowest speed.
When ready to assemble, be sure to repack the wheel bearings and use a moly grease. Also replace the grease seals!
Let's expand on part one. The 220mm upgrade will be an easy conversion on the 84 to 86 carbureted Shelby Chargers and Omni GLHs. The challenging one will be the 83 1/2 Shelby Charger. This car does not have a proportioning valve; it just has a metal block that serves to route the brake lines. DO NOT put 220mm drums on an 83 1/2 unless you are willing to basically install a complete 84 brake system. This can be done; it will just be more work.
The production Shelby Charger has a very balanced brake system. If anything, the front brakes need to catch up with the capabilities of the 220mm rears. The Shelby/GLH uses a 54mm piston for the front brakes. The next level is to convert to the Kelsey Hayes system used on most 85-90 Lancers, LeBarons, Shadows, etc. The easy way to identify the K-H system is that you can remove the entire rotor without unbolting the caliper bracket. Easy, right? All you need are the calipers and adapter brackets. By doing this upgrade you are increasing the brake pad (swept) area by a whopping 20% while retaining a 54mm piston. Since the L-bodies have about 75% of their weight on the front this will really show itself as a large decrease in stopping distance.
When doing this conversion be sure to use either OEM Chrysler brake pads or a premium aftermarket set such as Raybestos or Wagner Premium . Do not use the bargain brand from the local discount store. Also, have the rotors resurfaced and be sure to specify that you don't want them any thinner than .803 inch. This is important for safety as well as heat dissipation. The calipers should be rebuilt and inspected for any signs of corrosion. Make sure the calipers slide freely on the brackets, and use a good lube on them such as Sta-Lube Synthetic Caliper Grease #3301. Do not use this grease to assemble the piston into the caliper; use brake fluid when assembling all hydraulic parts.
When ready, use fresh brake fluid from a sealed container. DOT3 fluid is acceptable but DOT4 is superior. These are both glycol based and are compatible. DOT5 is a silicone based fluid that is great for cars that are stored or else driven very little. The hard part is that the brake system must be taken apart and cleaned of all traces of glycol fluid before silicone is added. DOT5 will not have the corrosion tendencies of the glycol fluid, but the consistency of quality is a question. If you are going to really use your brakes, stick with DOT4.
In part 3 we will talk about the beginning of an SLH (Stops Like Hell) package. Also covered will be the correct way to break in your new brakes.
Member John Spiva put bigger brakes on the front of his GLHS and is tickled with the results. He used the 1988 Shadow setup. He also discovered a brake fluid at a Ford dealer, #C6AZ-19542-AA that is a true 600 degree fluid! John surmises that "it must be for the hard-to-stop Fords." Ain't it the truth!
Okay, L-body lovers, here's the information you have been waiting for: the SLH packages! One note: please visit your dentist and have all fillings replaced with lighter material as the SLH3 package can dislodge heavier metal fillings!
Let's begin with SLH1. The L-body front brakes can be improved even more than the 54mm/20% upgrade covered in part II. The 84-90 Caravan uses a 60mm piston and a pad with another 20% increase in swept area over the Lancer/Shadow 54mm. This is a whopping increase that could only be achieved with aftermarket brakes on the other brands; Chrysler has made it easy for us. Go to a wrecking yard and get the calipers and adapter brackets from the Caravan. You will also need a master cylinder from a Daytona, Lancer, or LeBaron with a 24mm bore size. The reason for the master cylinder is that you need to move more fluid for the 60mm piston and keep brake pedal travel about the same. The best part is that everything bolts right on!
Once again, be sure to use premium pads and prepare everything as described in part II. The master cylinder should NOT be rebuilt! You may disassemble it and clean it with Brakleen, then check the rubber parts for wear and damage. Put in new seals if needed but don't hone the bore. This master cylinder is aluminum and hard anodized; honing it will remove the anodizing and will result in a unit that can fail at any time. Just follow the above steps and reassemble it using only brake fluid and it will be ready to give you great service.
SLH2 is primarily a disc brake conversion for the rear but it must be used with the 60mm front brakes. We will be using brakes from an 89-91 Daytona or LeBaron. The way to identify the correct unit is the nonvented rotor and the use of the small drum brake inside the rotor for the emergency brake. This is superior to the 87-88 setup which used a mechanical wedge/screw in the caliper to create an emergency brake. You will need the backing plates, rotors, hubs, calipers, and brake lines. Be sure to prepare everything as previosly described, and make sure the rotors are at least .409 inch thick after machining.
You will need a different master cylinder to move more fluid. This disc setup uses a 33mm piston, which is over two times the size of the wheel cylinder you replaced. Thus you need a master cylinder from an 84-92 Dodge truck D150 with a 1 1/8" bore. You will need adapters for your brake lines, available from Edelman, part #258340 and 258350 (check the local Napa store) or get the fittings from the same truck and put them on your lines. Make sure the lines are reflared with a double flare only. Any good brake or hose shop will be able to do this. You will also need the proportioning valve from a Daytona or LeBaron to make things work properly.
The last option, SLH3, is the installation of the vented rear disc brakes from an 89-91 Daytona (Shelby) and some LeBaron GTCs. This will be difficult to find but is for the enthusiast that needs that last little bit of stopping power. The vented setup uses a 36mm piston. Be sure to use the proportioning valve from the same car that donates the brakes, and make sure the rotors are no thinner than .797 inch after machining.
Once installed, your new brakes will need to be broken in. The reason is to set the polymer that binds the brake material together. You will want to bring the car to 60MPH, then apply the brakes hard enough that an empty coffee mug on the seat will tumble to the floor. Bring the vehicle down to about 30MPH, then gently accelerate (using only 1/3 to 1/2 throttle) back up to 60MPH. Again apply the brakes as described. Repeat this procedure 25 times, then park the vehicle for at least one hour to allow the brakes to cool. Be sure to roll the car forward a couple of inches every minute for the first 15 minutes of cooldown to ensure the rotors don't get hot spots on them. After the cooldown is completed, repeat the slowdown procedure five more times and your brakes will be ready for use!
There seems to be a lot of confusion about which calipers to use on both the 54mm and the 60mm upgrade. The key is to find the Kelsey Hayes calipers. As mentioned in part II, one way to identify the correct caliper and bracket is that you can remove the rotor without removing the adapter bracket. Another feature is that the Kelsey Hayes caliper uses one pin to mount onto the bracket; the undesirable ATE/Teves uses two pins.
Steve Johnson was kind enough to research the Chrysler part numbers for many of the applications and sent Robert a detailed list. To save space, let me give you a short list of the cars to look for to donate parts:
54mm / 20% conversion
60mm / 40% conversion
You will be safe with these applications. There is also some question about which rotors to use. You will retain stock Shelby/GLH L-body rotors. Do not use the rotors from the donor car. ( many Shelby Dodge gearheads have installed SLH-1 but also switched to minivan rotors. They seem to work just as well as the stock L-body rotors, so feel free to use them if you wish. What's the difference between the two? Chris Papademetrious writes: "the main difference between the L-body and minivan rotors is that the minivan rotors are ever so slightly narrower. The rotor plate itself isn't thinner, but the spacing between them (the vent width) is. In the two aftermarket rotors I compared (L-body and minivan), the vane spacing was identical; the only difference was the rotor thickness." Thus minivan rotors may be the way to go if your new pads are too thick to fit around your L-body rotors.)
The master cylinder is a challenge. I looked in the Raybestos catalog to see which car would have the 24mm master cylinder, yet at the wrecking yard it was very difficult to find. I have run across a unit that can be bought at your local Chrysler dealer. They call it a rebuild, but in reality it's a new unit! Here's a listing of all the "rebuilt" part numbers for the 60mm conversion:
Reman calipers
Reman M/C
Brake pads
Last modified: 10-11-09.