ghuncha
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| posted on 3/3/07 at 07:13 AM |
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handbrake solution?
well my friend has a problem, he has planned to build a mid engined ultra locost...hehe
he will be using mcpherson strut and all the engine tranny setup of a front engined car..... now the problem comes of hand brake....
is there any solution for it ?...
thanks
[Edited on 3/3/07 by ghuncha]
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miegru
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| posted on 3/3/07 at 07:49 AM |
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Afaik there is no regulation that states that the parkingbrake should be on the rearwheels. Citroen has it on the frontwheels in some models; at least
in the past they had.
So your friend could use, for instance, rearwheel calipers of some bigger sportier sedans (audi a4, bmw, etc.) on the front. For a lightweight car
these calipers should be more than sufficient.
Another solution is to add mechanical calipers to the rearwheel set up. RallyDesign sell these and your friend only needs to weld a bracket to the
strut.
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ghuncha
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| posted on 3/3/07 at 07:58 AM |
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well thanks for the reply, i think the mechanical calliper will be better, can the callipers be modified in anyway to accept hand brake...???
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RazMan
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| posted on 3/3/07 at 08:47 AM |
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You can put a hydraulic handbrake in the rear brake lines - saves any need for a separate caliper.... but I don't think they are very SVA
friendly.
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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nitram38
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| posted on 3/3/07 at 08:56 AM |
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Must be a mechanically operated handbrake only.
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miegru
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| posted on 3/3/07 at 09:08 AM |
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Hydraulic handbrake is not permitted for SVA, it has to be mechanical. At the SVA they spend a lot of time checking the flex in the system. From
cables to brackets; quite rigourous.
The mechanical ones from Wilwood ( www.rallydesign.co.uk ) are 39.50 a piece and 17.50 for a bracket if you want that. They are made for handbrake
use. Have never seen them 'live' though so cannot comment on performance, look or quality
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nitram38
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| posted on 3/3/07 at 09:10 AM |
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The hand brake calipers/drums must be held mechanically then (if you want to get picky!!!!)
A hydralyically held slave cylinder is not allowed.
[Edited on 3/3/2007 by nitram38]
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miegru
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| posted on 3/3/07 at 09:13 AM |
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Hi Mark,
Do you have epxerience with the VW system? Things like weight etc.
Is it ok to have an actuator directly linked to the brakecaliper? If so; what would be the weight penalty?
I have never like the handbrake solution in a seven; routing the cables thought the tunnel; somehow get past the diff etc.
An alternative would be interesting.
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britishtrident
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| posted on 3/3/07 at 09:31 AM |
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The holes in caliper brackets are in a range of standard pitches, but because of weight distribution front calipers on FWD calipers are always larger
than rear calipers. Sometimes the rear caliper from a larger car will fit the upright from a smaller front drive car -- for example Rover 216 rear
calipers fit Metro fronts.
BEWARE with using a fwd front suspension at the rear the problem of bump/roll steer will raise its ugly head. Toe-out on the loaded (outside) wheel
when cornering can be lethal espeically on a car with a rear weight bias and a low polar moment of inertia.
Also be aware that using existing front calipers on the rear will result in the rear wheels being grossly over braked.
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ghuncha
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| posted on 3/3/07 at 09:55 AM |
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well where i live(asia) we dont have the problem of SVA....lucky us.....
so no matter its hydrolic or elctric if it worls ok then its fine with us
quote:
You can put a hydraulic handbrake in the rear brake lines - saves any need for a separate caliper.... but I don't think they are very SVA
friendly.
can you please explain a bit.....
quote:
BEWARE with using a fwd front suspension at the rear the problem of bump/roll steer will raise its ugly head. Toe-out on the loaded (outside) wheel
when cornering can be lethal espeically on a car with a rear weight bias and a low polar moment of inertia
franckly all this went way over my head.. ..
can you explaina bit ...
quote:
Also be aware that using existing front calipers on the rear will result in the rear wheels being grossly over braked.
if we use th pressure regulator or what ever its callled, the small thing which comes in all cars which splits the pressure front/rear. more
to the front and less to the back....
thanks
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RazMan
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| posted on 3/3/07 at 10:57 AM |
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A hydraulic handbrake is really just a hand operated master cylinder with a ratchet stop which is plumbed into the brake circuit. It operates in such
a way that the system is kept pressurised as long as it is actuated.
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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ghuncha
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| posted on 3/3/07 at 11:26 AM |
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quote:
A hydraulic handbrake is really just a hand operated master cylinder with a ratchet stop which is plumbed into the brake circuit. It operates in such
a way that the system is kept pressurised as long as it is actuated.
well great thing... but one more thing... we just put a T and atach this with the rear brake line.. and the normal foor brake works ok still?
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RazMan
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| posted on 3/3/07 at 11:39 AM |
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That's it - it also saves a lot of mechanical linkages and cables. Personally I wouldn't trust it 100% for parking on hills etc though. If
the brake is applied when hot and as it cools it might gradually release the brake .... with inevitable results 
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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jambo
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| posted on 3/3/07 at 11:47 AM |
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i have an electric handbrake fitted although a tad expensive, but can be done.
 
Rescued attachment DSC01587.JPG
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ghuncha
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| posted on 3/3/07 at 12:27 PM |
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quote:
i have an electric handbrake fitted although a tad expensive, but can be done.
please some more details and from wher we can get it
thanks
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BenB
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| posted on 3/3/07 at 01:42 PM |
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quote:
Originally posted by jambo
i have an electric handbrake fitted although a tad expensive, but can be done.
Not so good for feathering handbrake turns though
Unless you press the button on and off very quickly!!!
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TheGecko
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| posted on 3/3/07 at 01:57 PM |
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I'm building a mid-engine clubman using a complete Corolla drivetrain (including suspension) in the back. I've looked at a number of
options for a handbrake. To be legal here in Australia (and I suspect similar regulations apply in most parts of the world) the handbrake must use an
independent method of application. Therefore, hydraulic handbrakes are NOT legal unless they actuate a separate set of calipers
I've just bought on eBay a pair of Series 4/5 RX-7 rear calipers which will fit over the thick ventilated discs found on the front of the
Corolla, and have a cable operated handbrake mechanism. I haven't got them yet, but here's the picture from the eBay listing:
[img][/img]
Other possible calipers are Series 2 MR2 Turbo (hard to find and expensive here) or earlier Subaru fronts (they have handbrake on the front
wheels).
Hope this is helpful,
Dominic
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