ed
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Registered: 10th Sep 03
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Introduction:
If you are planning of doing any modifications to you engine to get a higher power output you will definately need to upgrade your braking system. The brakes that come standard on Corsa's are also no good for people who like to drive thier car fast. They are small and tend to overheat very quickly. Luckly almost all Vauxhall brakes are interchangeable so you can get brakes off of a higher speced model or car.
There are two main types of brakes people go for when upgrading on a Corsa. Either the 2.0 brakes found on Astras, Cavaliers or Calibras (either 8v or 16 models, you want the ones with thick vented disks if possible) or V6 brakes found on Cavalier V6's, Calibra V6's, Omega 2.0 or V6's. The V6 brakes are the most powerful, but they weigh a lot more than the 2.0 brakes. Also, you will need to have the disk re-drilled to 4 stud and use a spiggot ring because all V6 Vauxhalls use 5 stud pattern hubs.
You can either buy a big brake kit from a parts retailer, many do kits, or you can source them from a breakers yard. I found my brakes from a breakers yard, they charged me £30 for the set. A brand new set from a parts retailer would be around £150 to £200.
I decided to go for the 2.0 brakes as I found them easily and I think they will be powerfull enough for my needs. When deciding what brakes you use you will need to check if they will fit under your wheels. Typically speaking V6 brakes will only fit under 16" wheels and above, 2.0 brakes should fit under 15" wheels and above.
Before:
1. Loosen the wheels nuts, jack the car up and support it on axle stands. You must be working on a firm flat surface, also make sure you use the correcly rated jack and axle stands - a Corsa wieghs around 1 tonne, so you will need a minimum 1 tonne axle stands and jack.
2. Remove the front wheels from your car to reveal the front brakes.
3. Using a hose clamp, clam the brake hose to prevent brake fluid leakage then undo the 11mm brake hose union from the caliper. Have a container ready and some cloth to wipe any spillages. If you get any brake fluid on your car wash it off immidiately with cold water. Brake fluid is an effective paint stripper.
4. Using a breaker bar carefully undo the 10mm allen key bolts that hold the caliper carrier to the hub carrier. These bolts are normally rust very tightly in place, they also have thread lock on them so you may want to wear some thick gloves.
5. Remove the caliper from the disk by simply lifting it away. This maybe a little difficult because the pads rub very lightly against the disk at all times making the fit tight.
6. Undo the phillips head retaining screw from the disk and pull the disk away from the hub. You may need to tap the back of the disk with a plastic faced mallet becuase the might have rusted in place.
You can see the differnce between the two brake setups now. The calipers and disks are much larger so you will get better stopping power!
7. Apply some copper grease to the hub and to the back of the disk to stop the two binding together.
8. Fit the disk onto the hub, you may need to tap the disk into place using a plastic faced mallet becuase the disks are tight fitting against the hub (make sure you align the disk correctly), then fit the phillips head retaining screw.
9. Fit the new caliper over the disk and screw in the 10mm allen key bolts into the hub carrier lightly by hand. Ensure the disk is on straight by turning it by hand and checking that it does not wobble from side to side.
10. Torque the 10mm allen key bolts to 95 Nm/70 lbf ft.
11. Re-attatch the brake hoses to the caliper by screwing in the union into the back on the caliper. Make sure you use new washers on either side of the union. Torque this up to 16 Nm/12 lbf ft.
Repeat stages 1 to 11 on the other side of the car.
You will now need to bleed the brake system. On ABS modles the curcuits are split front and back. On non-ABS models the brakes are split diagonally, so you bleed the front left caliper then the rear right and so on. However, if you clamped the brake hoses and did no loose a lot of brake fluid it is only neccesary to bleed the front brakes on ther own, the case would be the same on ABS modles as the rear brakes are on a different curcuit.
12. Get a clean jar and some clear hose that will fit over the bleed nipple. I used fuel line and a milk bottle.
13. Clean the bleed nipple and the surrounding area of the caliper and fit the pipe to the bleed nipple. Fill the bottle up with a small ammount of brake fluid to prevent air being sucked into the caliper, make sure the pipe is submerged in the fluid.
14. Top the brake fluid resevoir up and press the brake pedal several times to remove vacuum from the brake servo.
15. Loosen the bleed nipple by half a turn and get a friend to press down on the brake pedal slowly. Tighten the bleed nipple then get your friend to release the brake pedal. Top the brake fluid resevoir up every time, as if you allow air to be sucked into the brake system you will have to bleed the cuircuit again.
16. Observe the fluid coming from the bleed nipple in the clear pipe, once no more aire bubbles are surfacing you can stop bleedign that caliper and move onto the next. Tighten the bleed nipple to 9 Nm/7 lbf ft and replace the dust cap - discard any used brake fluid as it can never be re-used (DOT 4 can be contaminated by air, dust, water, condensation e.t.c...).
17. Once the system has been fully bled and you are satisfied that there is no air in the system you can re-fit the wheels and lower the car to the floor. Torque the wheel nuts to around 80 Nm.
18. Pump the brake pedal to presurise the system and allow the calipers to re-adjust. Check fluid level in the resevoir and top up if necessary. Then test your brakes at low speed. Make sure you can perform an emergancy stop and make sure the brakes preform normally.
After around 100 miles of driving, re-check the torque of all of the bolts you tightened as they may have come loose.
After:
All torque settings came from the Haynes Manual for a Vauxhall Cavalier, as I use Cavalier brakes.
If you do not understand any of the tasks in this tutorial do not attempt to fit new brakes to your car, a good knowledge of car mechanics is needed to tackle this task so it is best left to the professionals!
[Edited on 19-06-2005 by 1800ed]
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