matt_gsxr
|
| posted on 15/4/10 at 04:26 PM |
|
|
Which rear handbrake callipers instead of Sierra
hi there,
I have Sierra rear callipers, and they work alright but are heavy. So, I need something lighter.
The disk is 3.5kg (standard Sierra) and the calliper with pad and carrier another 3kg. Per side.
To fit them under a 13inch wheel I can change to a Mk3 Escort front disk (I have turned down the hub by the required few mm) and that is fine too, but
these disks are even heavier 4kg a disk.
I was thinking of changing to Mk4 Golf callipers. These are all alloy which is encouraging, but when I weigh them (2.4kg per side including pads and
carrier) they are only 500g or so lighter than the Sierra ones, and clearly massively over built for my application (my car is <40% the weight of
the Golf).
I have looked as Hi-spec who have an SVA approved £140+vat per side, and a nicer looking non-approved version at £155+vat and around 1kg per side. I
have also looked at Wilwood who also have some kits. But I don't want to spend 300-400 quid on brakes that don't even do much.
So what is the answer?
Rallydesign used to do a lightweight OEM caliper (~£70 a side) but I can't find that any more.
Anyone know a good option, lightweight (less than 2kg including pads), and cheap ?
BMW mini?
Peugeot 206?
VW polo?
Fiat 132?
I think I will go with those small (221mm diameter) early Fiesta front disks, which will save a few grams.
£25 per kg is what I am prepared to spend to save weight, but this is unsprung, so I can push the boat out a little.
Matt
|
|
|
|
|
phelpsa
|
| posted on 15/4/10 at 04:54 PM |
|
|
I'm pretty sure the 206 rear calipers are weighty cast ones not too dissimilar to the sierra ones.
EDIT: A quick ebay search reveals that they are actually the same as the 205 ones sorry.
http://cgi.ebay.co.uk/PEUGEOT-206-GTI-180-PUG-REAR-BRAKE-CALIPERS-205-307_W0QQitemZ270558222235QQ
EDIT #2: I think the rally design ones were infact the golf calipers.
[Edited on 15-4-10 by phelpsa]
|
|
|
matt_gsxr
|
| posted on 15/4/10 at 05:03 PM |
|
|
looks like alloy for the piston bit, but steel for the other end of it. Not so good on my brakes terminology!
I know that you know these units, so if they are too heavy then they are off the list.
Matt
|
|
|
Mal
|
| posted on 15/4/10 at 05:04 PM |
|
|
Focus Rear Calipers
The Focus rear disc is identical to the Sierra one. The caliper is of a similar general shape. It has a smaller piston diameter, but I think it is
worth looking at,
and would be easy to obtain.
Take a look here:
http://domain421029.sites.fasthosts.com/
If the above address does not work go to
the Brake Engineering websire and click on 'old website'
|
|
|
matt_gsxr
|
| posted on 15/4/10 at 05:14 PM |
|
|
Thanks Mal,
The focus one looks like the Sierra (same materials and same general shape) that I already have got fitted. I bet it would do the job, but it
doesn't look like I am going to get the big weight savings I am after.
I was hoping for some dainty little alloy thing of around half the weight of the Sierra ones.
The weather is nice this weekend so maybe I will take my spanners down to the breakers and have a look.
Matt
|
|
|
JC
|
| posted on 15/4/10 at 05:17 PM |
|
|
Matt,
The RD OEM caliper was a VW item, found on Golf, Passat, Leon, A4 etc - easily found in scrap yards or from German/swedish/french etc.
|
|
|
matt_gsxr
|
| posted on 15/4/10 at 05:29 PM |
|
|
JC
Do you know which years?
I remember picking up a rally design one at a show, and thinking it quite light.
I have a Mk4 golf one, and don't think it is light at all. Perhaps I am just getting weaker!
Matt
|
|
|
plentywahalla
|
| posted on 15/4/10 at 05:34 PM |
|
|
I did much the same search as you and ended up buying Compbrake R2's which are basically same as VW units 2.5 kgs inc pads.
They were doing them at a clearance price of £40 per side.
|
|
|
Minicooper
|
| posted on 15/4/10 at 05:43 PM |
|
|
quote:
Originally posted by matt_gsxr
JC
Do you know which years?
I remember picking up a rally design one at a show, and thinking it quite light.
I have a Mk4 golf one, and don't think it is light at all. Perhaps I am just getting weaker!
Matt
I weighed my Rally Design calipers and they were about 1.5 kgs per pair lighter than the Sierra calipers.
The main problem though was the fins on them no way would it go under a 13" wheel as they are much deeper than the Sierra unit
Cheers
David
One more thing they are a different mounting as well
[Edited on 15/4/10 by Minicooper]
|
|
|
iank
|
| posted on 15/4/10 at 05:45 PM |
|
|
quote:
Originally posted by phelpsa
I'm pretty sure the 206 rear calipers are weighty cast ones not too dissimilar to the sierra ones.
EDIT: A quick ebay search reveals that they are actually the same as the 205 ones sorry.
http://cgi.ebay.co.uk/PEUGEOT-206-GTI-180-PUG-REAR-BRAKE-CALIPERS-205-307_W0QQitemZ270558222235QQ
EDIT #2: I think the rally design ones were infact the golf calipers.
[Edited on 15-4-10 by phelpsa]
The rally design ones are indeed golf rears iirc.
Edit: Just looked and I can't find them on rallydesigns website anymore. If asked to guess I'd say Mk4 from the pictures on
brakesint's website. http://www.brakesint.co.uk/
The 206 ones are the same as 106/Saxo rear calipers. Cost £73.63 each+VAT new from brakesint. (p/n BCA1086 and BCA1087)
[Edited on 15/4/10 by iank]
--
Never argue with an idiot. They drag you down to their level, then beat you with experience.
Anonymous
|
|
|
phelpsa
|
| posted on 15/4/10 at 05:48 PM |
|
|
I know they arent so common, but what about one of the little lightweigh japanese cars. I dont even know whether they have rear discs but suzuki
capucino, daihatsu charade gti, daihatsu mira, suzuki alto etc. They all run tiny discs and 12 or 13 inch wheels.
|
|
|
matt_gsxr
|
| posted on 15/4/10 at 06:02 PM |
|
|
Good call on the COMPBRAKE site. £98 for a new PAIR. For that money it isn't worth getting the Sierra ones reconditioned (IMO).
Regarding little japanese stuff;
Honda Jazz = steel
suzuki Capacino = similar to 206
suzuki Alto = drums
Daihatsu charade GTi = drums
I am thinking of Lupo GTi as these are similar to the Mk4 Golf ones, but can only be lighter (surely).
Matt
|
|
|
iank
|
| posted on 15/4/10 at 06:08 PM |
|
|
Lupo GTi ones look identical to Mk4 golf ones with 34mm rather than 38mm pistons.
--
Never argue with an idiot. They drag you down to their level, then beat you with experience.
Anonymous
|
|
|
JC
|
| posted on 15/4/10 at 06:12 PM |
|
|
yes, mk4 golf, mine came off the passat before the present model, £50 for a decent pair from local scrappy!
|
|
|
daniel mason
|
| posted on 15/4/10 at 06:14 PM |
|
|
mazda mx5??
|
|
|
britishtrident
|
| posted on 15/4/10 at 06:57 PM |
|
|
With a bike engine your car will have a rear weight bias if you rear calipers much smaller than the Sierra you may end having to fit front calipers
with a smaller effective hydraulic area.
The saloon Golf has 38mm bore calipers which are quite big for the rear of FWD but quite a lot (5mm) smaller than the Sierra rear.
The Golf Mk4 Estate has 41mm bore rear calipers only 2mm smaller than the Sierra but I don't know if the estate has alloy calipers.
Saving unsprung weight is important but so is effective balanced braking.
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
|
|
|
phelpsa
|
| posted on 15/4/10 at 07:21 PM |
|
|
quote:
Originally posted by britishtrident
With a bike engine your car will have a rear weight bias if you rear calipers much smaller than the Sierra you may end having to fit front calipers
with a smaller effective hydraulic area.
The saloon Golf has 38mm bore calipers which are quite big for the rear of FWD but quite a lot (5mm) smaller than the Sierra rear.
The Golf Mk4 Estate has 41mm bore rear calipers only 2mm smaller than the Sierra but I don't know if the estate has alloy calipers.
Saving unsprung weight is important but so is effective balanced braking.
But in running a bias box you can compensate for the piston diameter with different size master cylinders pretty cheaply (change from a 0.75" to
0.7" ) and fine tune with the bias mechanism.
[Edited on 15-4-10 by phelpsa]
|
|
|
matt_gsxr
|
| posted on 15/4/10 at 07:30 PM |
|
|
mx5 is steel, but looks more dainty than a Sierra one.
If lupo Gti is the same as the "standard" VW/AUDI one then that is no good.
I was hoping that there might be a scaled down version of the VW one out there, but apparently not.
Good point on brake balance and noted.
I might just go for the smallest disk that I can, and take a file to the Sierra callipers to remove anything "spare". The maximum
pressure and the shock loads to the pedals are reduced so much with the ABS and servo removed.
Matt
|
|
|
britishtrident
|
| posted on 16/4/10 at 06:58 AM |
|
|
quote:
Originally posted by phelpsa
But in running a bias box you can compensate for the piston diameter with different size master cylinders pretty cheaply (change from a 0.75" to
0.7" ) and fine tune with the bias mechanism.
[Edited on 15-4-10 by phelpsa]
Bias boxes only really work well when the bar is working close to the centre position. If the bar is too far off centre you end changing master
cylinder bore sizes. It is really best to get the relationship between the front and rear caliper sizes in the right ball park.
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
|
|
|
phelpsa
|
| posted on 16/4/10 at 01:41 PM |
|
|
I said its quite easy to change master cylinder sizes and then fine tune with a bias bar. Most people run a 0.625" front and 0.75" rear to
get the correct balance using sierra rear calipers. You can change to a 0.7” or 0.625” rear to compensate for a small rear piston size. Another
option is to fit softer front springs and fit a stiffer ARB as well to try and encourage some more weight transfer under braking.
|
|
|
