DIY - Rear Disc Brake Upgrade
CAUTION!!! I do not take any responsibility for improper installation, damaged parts, or bodily harm from this product or guide. If you do not feel comfortable with this conversion, stop what you are doing and outsource a reputable mechanic. Buy quality parts. The purchaser and vehicle owner are responsible for correctly torquing all bolts and fittings to their factory spec, per the vehicles manufacturer, making sure everything is tight, secure, and safe. I want everyone to be safe and to enjoy their new rear disc brakes. The last thing you need is a rear wheel to fail or fall off. Be safe, torque correctly and ride smart!
*10/13/25 - To order these custom brackets, use my store link: https://g1preludes.myshopify.com/
Fits the following model cars:
· 76-81 Honda Accord (3dr/4dr)
· 82-85 Honda Accord (3dr/4dr)
· 80-83 Honda Civic (3dr/4dr/Wagon)
· 79-82 Honda Prelude (2dr)
· 83-87 Honda Prelude (2dr)
· 80-85 Honda Quint or Quintet (dr)
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PARTS NEEDED:
- (4) New Spindle Mounting Hex Bolts
o M10x1.5-30, JIS Grade 10.9 / '79-83 Prelude & '80-83 Civic Models (Included In Kit)
o M8x1.25-30, JIS Grade 10.9 / '83-87 Prelude & '76-85 Accord Models (Not Included in Kit)
- (2) M10x1.5-25, JIS Grade 10.9 Caliper Bracket Mounting Hex Bolts
- (2) New / Remanufactured 7CLP13S 30mm OEM Rear Brake Calipers w/ Brackets From Select Models:
o USDM Acura Integra 2dr/4dr '90-01 (All Models exec. Type R)
o USDM Honda Civic 2dr Si '99-00
o USDM Honda Civic 3dr Si '92-95
o USDM Honda Civic ’90-91 EX Sedan
o USDM Honda CRX 88-91 Si
o USDM Honda Civic 2dr/4dr EX ABS '92-95
o USDM Honda Del Sol Si or Vtec '93-97
- (2) 1984-1987 Honda Prelude Rear Disc Rotors (9.4"Dia)
o OEM #42510-SF0-000
- (8) 1984-1987 Honda Prelude 12mm Threaded Wheel Studs
o OEM #90113-SA-025 or 90113-SM1-005
- (8) 1984-1987 Honda Prelude 12mm Lug Nuts
- (2) New Inner Wheel Bearings with Races
o OEM #91053-671-008
- (2) New Outer Wheel Bearings with Races
o OEM #91052-671-008
- (2) Hub Outer Seals
o OEM #91252-692-931
- (2) M4x25 Split Cotter Pins or Equivalent
- (2) New Rear Brake Lines (USDM '94-01 Integra Models are ideal)
- (2) New Rear Brake Lines (Rubber or Steel),
o Stock 94-01 Acura Integra 2dr length worked great
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Wear protective PPE, you will be working with a lot of loose brake dust. Organize all your parts as you disassemble them, so reassembly is easier.
Follow your model Honda diagram above before continuing below:
Make sure the e-brake is disengaged! Disassemble the e-brake cables first from each drum. Remove the grease cap and rear wheel. Remove the cotter pin and pin holder. Remove the spindle nut. Remove the outer drum casing. Sometimes a mallet or small hammer is needed to break the drum free. This part can become rusted to the pads. Once free, carefully wiggle the drum off the pads using a prybar or flat head. The inner and outer spindle bearings will come off with the drum. Remove the hard brake line from the rear of the drum, using a metric flared brake wrench. Due to the age of our cars, this part can be tricky as the metal has become soft or and will round easily. Vise grips can be carefully used if a flared wrench does not work. Once the line is disconnected, loosen the four main hub bolts inside the drum around the spindle. The entire drum can now be pulled off from the spindle, while no springs or extra hardware need to be removed. For ’79-82 Prelude and Civic Models, the wheel spindle will detach from the rear knuckle. For Accord and 83-87 Prelude Models, the spindle is part of the knuckle and cannot be detached. If your spindle can be detached, it can be slightly frozen to the knuckle, so a light tap of a mallet or small hammer will free it. Be sure to keep the spindle clean and to not damage it. If you have an air compressor handy, blow off any loose dirt away from you and brush off all the mating surfaces. Be sure everything is cleaned before reassembling. Brake cleaner at this point is your best friend and I almost guarantee a good cleaning is needed.
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WHEEL SPINDLE PREP:
For ’79-83 Honda Prelude and Civic Models, install the spindle back onto the knuckle, then attach the rear brake adapter bracket over the spindle. While holding both parts, align the four holes and use new or existing bolts to tighten everything together. Torque each bolt to 40 lb-ft. M10x1.25x30 bolts are used for these models.
For Honda Accord and ’83-87 Prelude Models, install the rear brake adapter bracket over the spindle and use new or existing bolts to tighten everything together. Torque each bolt to 20 lb-ft. M8x1.25x30 bolts are used for these models.
ROTOR PREP:
Carefully take your new rotors and install the inner and outer bearing races using a driver, mallet or press. A small drop of grease around each race before installing helps the install greatly. Be sure to slowly drive them into the rotor and stop when they start to resist and are flush with their seated edges.
Next install the four lug nuts into each hole on the rotor. A hydraulic press will be your best tool, while you can do the alternative trick of using a lug nut on the opposite side and impacting the nut. This will tighten the nut, bringing the stud through until it is seated. Be sure each stud is all the way through matching its length for all four.
ROTOR / HUB INSTALLATION:
Pack multipurpose grease inside the rotor, between the races using a generous amount. Grease the inner bearing and then place the bearing onto the inner race. While holding the rotor and bearing together, tap the outer hub seal into the back of the rotor using a mallet or small hammer. Tap the seal using a “X” pattern to prevent damage. Slip the rotor/hub over the spindle, aligning the bearing and hub seal. Grease and install the outer bearing. Install the hub washer and spindle nut until hand tight.
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WHEEL BEARING ADJUSTMENT:
When retightening the spindle nut on your new rear disc brake assembly, follow these steps EXACTLY. Not following these steps could lead to bearing failure or noise. This will ensure the bearings are snug and correctly torqued onto the spindle to OEM spec.
1. Apply grease or oil on the spindle nut and spindle threads.
2. Install and tighten the spindle nut to 25 N-m (2.5 kg-m, 18 lb-ft) and rotate the brake disc 2-3 turns by hand, slightly loosen the nut and then retighten the spindle nut back to 25 N-m (2.5 kg-m, 18 lb-ft).
3. Repeat Step 2 if nut seems too loose, it should have a little resistance to it.
4. Slightly loosen the spindle nut once more Do not loosen beyond this!!!
5. Retighten the spindle nut to 5 N-m (0.5 kg-m, 4 lb-ft).
6. Set the pin holder so slots will be as close as possible to the cotter pin hole on the spindle
7. Tighten the spindle nut just enough to alight slot and hole, then secure with a new cotter pin.
8. Lightly mallet back on the brake hub/drum cap back on.
Emergency Brake Installation
The E-brake cable is currently not an easy fix for now. Richard Voaden utilized the old drum cable attachment and welded it to the calipers spring return. He mentioned it worked but had to loosen the rear brake cables almost completely from the adjuster to achieve a successful pull. Lowered cars will be affected more by this due to the suspension travel. A picture of his setup is below.
I personally found you can utilize the original Brake Lever Joint Honda Part# 43440-SA0-971, found only on 1982 Honda Prelude and ‘82-83 Honda Civic Drum Brakes. I’ve had good luck with mine from this setup (figure 3) and it works extremely well. Little modification is needed. You will need to grind some of the sidewall off the joint for the cable to pull straight and not at an angle (figure 4). The calipers will have a small hole for their original e-brake cable to mount, that will need to be drilled larger to a 5/16” hole to install it. Once installed, lower your car and adjust the cables with the rear LCA’s relaxed at normal shock height.
I’m currently creating an after-market solution for this. I will offer this for sale soon.
Troubleshooting – If the rotor edge is rubbing against the caliper bracket and not centered, there are two possible reasons for this. A reman caliper and its bracket could be slightly bent. Unfortunately, with unskilled mechanics and people who like hammers, you may receive a bracket that is not square and has been beat senseless when it was originally removed. I ran into this myself. Slightly bend the bracket back with your body strength and see if that corrects it. Second, all your mating surfaces may not be clean or debris free, resulting in the adapter plate to not sit flush to the knuckle, or the rotor is not install all the way on the spindle after proper torquing. Remember the rear hub seal of your new rotor should be 1-2mm away from the adapter plate when installed correctly and your adapter sits on top of the spindle.
