itsawindupuk
|
posted on 10/2/16 at 10:31 AM |
|
|
Decent handbrake caliper for solid discs
Hiya guys. Anyone know of any good handbrake calipers for solid discs? I've looked at the wilwood ones and they mostly use vented. Could I use
a spacer? Or are there other options? I'm happy to use a spot caliper but heard the wilwood one sucks but can't find any others with
reviews. It's for my MGB which has 4 pot wilwoods on front and I'm doing a disc conversion at the rear.
Thanks
|
|
|
loggyboy
|
posted on 10/2/16 at 10:42 AM |
|
|
Why not just convert to an OE caliper with handbrake built in? Sierra & Golf are popular choices.
Mistral Motorsport
|
|
nick205
|
posted on 10/2/16 at 10:45 AM |
|
|
VW Golf rear calipers seem popular and should be widely available.
I've just sold my Passat B6, which had an electric parking brake via a dash button - levers seem very out dated to me now
|
|
Neville Jones
|
posted on 10/2/16 at 10:59 AM |
|
|
Golf, Passat, Seat, Skoda, all VAG group.
If you want to get all technical and balance up the braking effort before using a balance bar, then these come in a few different piston sizes, to
give differing force.
They are a bit lighter than the Sierras as well, being ali.
Cheers,
Nev.
|
|
itsawindupuk
|
posted on 10/2/16 at 10:59 AM |
|
|
Cheers for the replies guys. I thought about those and will probably end up with that kind of option but being a tart I kind of wanted something to
aesthetically compliment the fronts lol. The electronic brake sounds interesting, I'm building a new wiring loom for the car so that could be
integrated.
|
|
mcerd1
|
posted on 10/2/16 at 11:19 AM |
|
|
HiSpec do a handbrake caliper as a direct replacement for sierra ones - but they aren't cheap (and I've not always heard good things about
the customer service either...)
-
|
|
nick205
|
posted on 10/2/16 at 12:58 PM |
|
|
I believe the Passat's EPB (Electronic Parking Brake) uses an electric motor to pull a cable to operate the brake - you can hear it when
activating the brake.
Interestingly, the first Passat I had (57 plate) had this plus a button by the gear stick to activate "Auto-Hold" for hill starts. The
second Passat I had (57 plate) didn't have this, but if you activated the EPB for hill hold it let you drive away and released the EPB by
itself. Both approaches worked fine and the extra space in between the front seats due to the lack of lever was very welcome.
On my MK Indy I utilised the Sierra rear drum brakes with a cable operated hand brake. Since it was used infrequently and parked on flat ground I used
to leave the hand brake off and chock the rear wheels. This saved the drums jamming on, which can be a PITA to release.
|
|
nick205
|
posted on 10/2/16 at 04:29 PM |
|
|
Knowing VAG's like for cost saving and component sharing I suspect you can get the same rear calipers on a number of VAG vehicles. The one
I've seen used are alloy and look OK too.
|
|
Sam_68
|
posted on 10/2/16 at 06:46 PM |
|
|
quote: Originally posted by nick205
I believe the Passat's EPB (Electronic Parking Brake) uses an electric motor to pull a cable to operate the brake - you can hear it when
activating the brake.
HiSpec showed a caliper with a motor mounted on the caliper itself, to provide an electronic handbrake, at this year's Autopsports show. Still
quite a light assembly, even with the motor (it's a sliding caliper, so just one piston and one set of pads serving for both hand and
footbrake). They're just in the process of costing it for production, they said, but IIRC a figure of around £185 per caliper was anticipated.
|
|
Dingz
|
posted on 10/2/16 at 07:28 PM |
|
|
Use MGF ones, keep it in the family as it were.
I think I have an old set somewhere?
Phoned the local ramblers club today, but the bloke who answered just
went on and on.
|
|
obfripper
|
posted on 10/2/16 at 09:25 PM |
|
|
The passat caliper has an integrated motor, it's not much heavier than an ordinary caliper, other models also have a cast iron version that is
heavier.
The aluminium passat version does have one caveat, they slowly corrode, the pressure of which eventually cracks the plastic motor housing letting
water into the motor/electrical connector followed by failure, this probably wouldn't be an issue with a kit kept in the dry.
It wouldn't be too hard to use in a kit application with some ic's, relays and auto resetting polyfuses, using basic operation
knowledge.
Under normal operation, the control unit operates the motor in the apply direction to a preset current(iirc 20a per caliper) then cuts off, and in the
release direction for a preset time period (iirc 2 seconds).
When released the piston remains in the same position, the internal mechanism is backed away from the piston, not affecting pedal travel/feel.
To change pads the motor is operated in the release direction until it reaches a stop, then the piston is pushed in as you would with a front
caliper.
After pad replacement the motor is operated in the apply direction to the cut off point, then released to seat the pads and take out any free play.
There are other functions the oem control unit is capable of(such as pad wear warning) that would not need to be replicated.
It's unlikely that the oem control unit could be used with a kit, as it relys on can bus data from multiple ecu's to operate which would
be a nightmare to try and simulate.
A safety system so the brake could not be accidentally released is essential, ie foot brake application required to activate release switch, or 2
separate switches operated together to release, mirroring the function of oem systems.
A handbrake 'on' lamp would be tricky to implement as it will need to store the status of the caliper while powered off, it would not be
an mot issue though.
Most requirements for the mot would be covered by the caliper design itself, the epb malfunction lamp function would be a null point as you
won't have one (there is no rfr for epb lamp missing), and the brake effort would be tested as normal in brake rollers.
I can see a decelerometer test being impossible as the caliper will apply to a lock (this is only an issue if you have a plate lsd), oem systems
don't apply the handbrake mechanism while moving, they apply the service brake via the abs unit instead so also cannot be decelerometer
tested.
I'm not sure if there will be any updated mot testing procedure as the electronic handbrakes are becoming the norm on a lot of cars, at present
only a mechanical handbrake is tested in regards to accidental release, it may change to include this for electronic systems.
I don't know how the iva deals with home brewed epb systems, also the iva regs may give some idea of what changes might happen with the mot.
Dave
|
|
itsawindupuk
|
posted on 10/2/16 at 10:31 PM |
|
|
quote: Originally posted by Dingz
Use MGF ones, keep it in the family as it were.
I think I have an old set somewhere?
Dingz, I did think about the F ones and looking at them online looks like they have a "pull" rather than turn for the handbrake mechanism
which is how the current drums work. Could be interested in your old ones
Adam
|
|
itsawindupuk
|
posted on 10/2/16 at 10:32 PM |
|
|
quote: Originally posted by obfripper
The passat caliper has an integrated motor, it's not much heavier than an ordinary caliper, other models also have a cast iron version that is
heavier.
The aluminium passat version does have one caveat, they slowly corrode, the pressure of which eventually cracks the plastic motor housing letting
water into the motor/electrical connector followed by failure, this probably wouldn't be an issue with a kit kept in the dry.
It wouldn't be too hard to use in a kit application with some ic's, relays and auto resetting polyfuses, using basic operation
knowledge.
Under normal operation, the control unit operates the motor in the apply direction to a preset current(iirc 20a per caliper) then cuts off, and in the
release direction for a preset time period (iirc 2 seconds).
When released the piston remains in the same position, the internal mechanism is backed away from the piston, not affecting pedal travel/feel.
To change pads the motor is operated in the release direction until it reaches a stop, then the piston is pushed in as you would with a front
caliper.
After pad replacement the motor is operated in the apply direction to the cut off point, then released to seat the pads and take out any free play.
There are other functions the oem control unit is capable of(such as pad wear warning) that would not need to be replicated.
It's unlikely that the oem control unit could be used with a kit, as it relys on can bus data from multiple ecu's to operate which would
be a nightmare to try and simulate.
A safety system so the brake could not be accidentally released is essential, ie foot brake application required to activate release switch, or 2
separate switches operated together to release, mirroring the function of oem systems.
A handbrake 'on' lamp would be tricky to implement as it will need to store the status of the caliper while powered off, it would not be
an mot issue though.
Most requirements for the mot would be covered by the caliper design itself, the epb malfunction lamp function would be a null point as you
won't have one (there is no rfr for epb lamp missing), and the brake effort would be tested as normal in brake rollers.
I can see a decelerometer test being impossible as the caliper will apply to a lock (this is only an issue if you have a plate lsd), oem systems
don't apply the handbrake mechanism while moving, they apply the service brake via the abs unit instead so also cannot be decelerometer
tested.
I'm not sure if there will be any updated mot testing procedure as the electronic handbrakes are becoming the norm on a lot of cars, at present
only a mechanical handbrake is tested in regards to accidental release, it may change to include this for electronic systems.
I don't know how the iva deals with home brewed epb systems, also the iva regs may give some idea of what changes might happen with the mot.
Dave
I think there would be a market for something that could use the epc callipers. After a little research I think id struggle with the wiring if it
wasn't a simple case of on and off.
|
|
big-vee-twin
|
posted on 11/2/16 at 08:37 AM |
|
|
I have 4pot Wilwood up front colour black and powder coated (high temp) black Sierra hand brake calipers on the rear - was the simplest solution after
considering others. Look OK works fine.
Duratec Engine is fitted, MS2 Extra V3 is assembled and tested, engine running, car now built. IVA passed 26/02/2016
http://www.triangleltd.com
|
|
mcerd1
|
posted on 11/2/16 at 10:28 AM |
|
|
I used these guys to recondition a few sets of calipers and paid the little bit extra to get them in a long lasting coloured finish (black for the
tintop) - the guys are really helpful and pretty quick too
And they supply the parts if you want to rebuild them yourself.
http://www.biggred.co.uk/
The finish is never going to be as good as fancy alloy calipers, but its not bad - and on the tintop they still cleaned up pretty well after 3 years
of abuse (I never wash my tintops either...)
[Edited on 11/2/2016 by mcerd1]
-
|
|
b14wrc
|
posted on 11/2/16 at 12:30 PM |
|
|
Hi,
It might be of little interest, but ive just bought some Omega V6 rear calipers for my locost. These are twin pots with 40mm diameter pistons.
Im planning on making a central expansion plate, to allow for a 22mm wide disc and fabricating my own hand brake system in the caliper - i saw one
willwood do on a four pot....
As usual im experimenting but i reckon it will compliment my front brake set up of Brembo 4 pots and 305mm discs....
I will post photos at the weekend if its of interest. Electronic hand brakes dont do it for me im afraid, thats why i just bought a GT86, wanted a new
car but somthing that didnt have too much assistance - like my old Lotus Elise. Seen many of these on ebay while i was researching what i wanted.
Rob
20vt powered rear engined locost
|
|
nick205
|
posted on 11/2/16 at 03:37 PM |
|
|
quote: Originally posted by obfripper
The passat caliper has an integrated motor, it's not much heavier than an ordinary caliper, other models also have a cast iron version that is
heavier.
The aluminium passat version does have one caveat, they slowly corrode, the pressure of which eventually cracks the plastic motor housing letting
water into the motor/electrical connector followed by failure, this probably wouldn't be an issue with a kit kept in the dry.
Hmmm, I didn't know that about the motor in the caliper, makes sense.
In operation on the Passat you have to have the foot brake on to activate the EPB. It will however release itself without the foot brake being on for
hill starts etc.
|
|