Upgrading your classic BMW from drum to disc brakes involves selecting high-quality components such as compatible calipers, vented or solid rotors, and brake pads suitable for your driving habits. Ensure metric wrenches, sockets, a torque wrench, and a brake bleeder kit are available. Refer to the BMW service manual for specific torque settings and installation instructions. Begin by removing the wheel and drum, then fit the caliper bracket and new rotor onto the hub. Secure the caliper, install stainless steel brake lines, and bleed the system. Test the upgrade by evaluating stopping distance and pedal firmness; more insights can deepen understanding.
Understanding Brake Systems
To maintain or improve a classic BMW, understanding the brake system is key. Disc brakes work better than drum brakes. They stop the car faster and handle heat better. If you switch from drum to disc brakes on an older BMW, it can make driving safer.
Disc brakes use a caliper to press brake pads against a disc. This turns the car's movement into heat, which then goes into the air. Drum brakes, on the other hand, use shoes to press on the inside of a drum. They don't manage heat as well.
When upgrading brakes, check things like rotor size, caliper type, and materials. Vented rotors cool down faster than solid ones and are less likely to lose braking power during long use. Ceramic or carbon-composite pads can make braking even better but might cost more.
Motorsports often switch to disc brakes because they work well. For classic BMWs, think about how new brakes will fit and perform with the car. This ensures the car keeps its original feel while getting better brakes.
Gathering Necessary Tools
To upgrade the brake system on a classic BMW, start by gathering the right tools. These tools help make the switch from drum to disc brakes easier.
You'll need a set of metric wrenches and sockets for BMW's parts. A torque wrench helps you tighten bolts just right so they won't be too loose or too tight. Get brake line wrenches that fit snugly on brake lines to avoid damage.
A brake bleeder kit helps get rid of air in the brake lines. This keeps the brakes working well. Use C-clamps to press brake calipers, and a rubber mallet to gently loosen parts without breaking them.
Jack stands and a hydraulic jack are used to lift the car safely. For tough jobs, an impact wrench and angle grinder can help take off rusted parts or change parts if needed.
Selecting the Right Parts
With the right tools ready, let's pick the best parts to upgrade your classic BMW's brakes. Getting the right parts makes sure your car stops well and stays safe. First, know your BMW's model details so you pick parts that fit perfectly.
- Brake Calipers: Use good calipers made for your BMW. Brands like Brembo and Wilwood work well and last long. The calipers should fit your wheels and suspension for smooth operation.
- Brake Rotors: Choose solid or vented rotors based on how you drive. Vented rotors cool down faster, which is good for spirited driving or larger cars.
- Brake Pads: Pick pads that suit how you drive. Ceramic pads are quiet and make less dust. Semi-metallic pads stop better, especially for high-performance driving.
- Brake Lines: Stainless steel brake lines make the pedal feel firmer. They don't expand like rubber ones, giving you steadier braking.
Each part helps the brakes work well, making sure your car stops smoothly and safely.
Preparing for the Upgrade
Get ready for your upgrade by gathering tools like a socket set, screwdrivers, brake fluid, and a jack with stands.
Make sure your workspace has enough light and room so you can move safely around your classic BMW. This setup helps you switch from drum to disc brakes smoothly.
Check your BMW's service manual for any special needs or limits related to your model.
The manual gives details on torque settings and unique parts that may need extra care, which helps avoid mistakes.
Look at the parts you've got.
Ensure the rotors, calipers, and brake pads fit your car's make and model.
Check these parts closely for any problems because defects can affect safety and how well they work.
Step-by-Step Installation
Once you have everything ready and all parts match your BMW model, you can start changing your drum brakes to disc brakes. Remove the wheel, brake drum, and any connected parts. Follow your BMW's guide to avoid breaking anything.
- Caliper Bracket Placement: Place the caliper bracket on the wheel hub. Make sure it lines up with the mounting points. Fasten it tight with strong bolts as per the manufacturer's instructions.
- Rotor Installation: Put the new rotor onto the hub. Check that it fits properly and moves smoothly. Ensure it works well with the chosen caliper and brake pads.
- Caliper Attachment: Fix the caliper to the bracket using the specified bolts. Ensure the caliper pistons pull back correctly to make room for the brake pads.
- Brake Lines Connection: Swap the old brake lines with stainless steel braided ones for improved performance. Bleed the brakes to clear out any air for a steady pedal feel.
Testing and Adjustments
Start by looking at the new disc brake system to see if anything is out of place or loose. Check the calipers, rotors, and brake lines to make sure they are tight and in the right position. If things aren't lined up right, the brakes won't work as well and parts could wear out unevenly.
Make sure the brake pads fit well and that the rotor is clean.
Press the brake pedal while the car is still. A strong pedal means everything is working well, but if it feels soft, there might be air in the system or not enough brake fluid. You might need to bleed the brakes to fix this.
Drive slowly in a safe area to test the brakes. Press them gently and listen for any odd sounds like squeaking or grinding. These could mean the pads or rotors are worn out.
Check how long it takes for the car to stop and see if it matches what you expect from a good brake system. You might need to make some tweaks to get everything working just right.
People Also Ask
How Does Upgrading to Disc Brakes Affect the Car's Resale Value?
Upgrading to disc brakes can make a classic car safer and better at stopping, which might make it worth more to some buyers. But, some people like cars to stay original, so they might not want it if you've changed the brakes.
Are There Any Legal Considerations When Modifying Brake Systems on Classic Cars?
When changing the brakes on old cars, it's important to follow local laws and safety rules. If you don't, you might have to pay fines or lose your insurance. This can make it hard to drive or sell the car.
What Is the Estimated Cost of Upgrading From Drum to Disc Brakes?
Switching from drum to disc brakes usually costs between $500 and $1,500. This depends on your car type and the quality of parts and labor. For older cars, you might have to pay extra for special changes to make everything fit.
How Does the Brake Upgrade Impact the Car's Insurance Policy?
Changing a car's brakes from drum to disc might make insurance cost more because the car can perform better. It's important to tell your insurance company about the change so they can adjust your coverage and costs if needed.
Can Drum to Disc Brake Conversion Kits Affect the Car's Authenticity in Classic Car Shows?
Changing drum brakes to disc brakes on a classic car can make it less original. In car shows, judges want cars to be like they were when first made. If you change the brakes, it might lose points and be worth less in competitions.