Jump to content

Front Break Upgrade For Sierra


Recommended Posts

Hello Friends,

 

I have standard Sierra disk breaks with no servo on the front of my Roho kit car. Basically the breaks are rubbish at stopping the car with the back drum breaks skiding firstly.

 

As I see it I can upgarde the pads only (what are the best pads), replace the calipers and pads with maybe the 4 pot type (what is the best resonably prices calipers and what suppliers?), or maybe fit a servo (probably more difficult and not much room under the bonnet as V8 engine).

 

Which is the most sensible way forward that won't cost me a fortune. I don't want to race the car, but I do want to be able to stop the thing with some confidence.

 

Many Thanks

 

Kevin

Edited by MendipWursel
Link to post
Share on other sites

I have standard 2 litre disk brakes fitted to my 2B, with the smaller drum brakes at the rear (from a 1.8 hatchback), I have no servo either & the brakes can lock up Toyo 888s on the front, without the back locking, & these are sticky tyres.

 

I have looked at upgrading the brakes in the past, but decided there is really no point if I can already lock the wheels.

The standard set up will work really well without a servo provided it is in good condition, but it does need a real shove on the pedal.

Look at fitting a pressure reducing valve to the rear line instead, and maybe getting recon calipers & master cylinder. Far cheaper than aftermarket gear.

Link to post
Share on other sites

I agree with Bob, best (& easiest bet) is to fit the standard Sierra proportioning valve in the rear brake line.

 

This will allow full pressure to the rears under normal braking, but the harder you are stopping (weight transfer from the rear onto the front, reducing the effectiveness of the back brakes by making them lock quicker) the less pressure it allows in the rear line, effectively moving the bias to the front.

 

There seems to be a lot of people that don't like them, but they are are simple reliable device to maximise braking stability/effectiveness. I ran without one for a while with my twin master cyliner/bias bar/wilwood setup and it was rubbish. Re-fitted it and brakes are perfect again :)

Link to post
Share on other sites

I have a similar setup and to compensate for the lack of a servo I fitted a master cylinder with a smaller bore than the one from the Sierra.This gives a higher pressure for the same pedal force but involves a longer pedal travel.

Link to post
Share on other sites

Hi re brakes I run std drums /linings at the rear no apportioning valve +HI SPEC 4 POT CALIPERS and 260 mm vented discs with HiSpec recomended pads up front.It works for me! ,also ALL brake pipes are stainless braided PTFE,not the ultimate but have served me v well over the last 10 /15000 miles HTH MOWERMAN .

Link to post
Share on other sites

Kevin, the problem is probably not your front brakes but the rears, and as others have said you will need to fit a pressure reducing valve in the rear system, The standard Sierra one relies on inertia and the fact that a fully laden Sierra will dive at the front under braking. so it can be a bit tricky to get it set at the right angle, you could fit an adjustable one and try a few adjustments, as your car is on the road it should be ok, it wasn't allowed to be adjustable at SVA time.

Link to post
Share on other sites

it could also be because the sierra did not origianally have a V8 under its bonnet, all that extra weight on the front of the vehicle will over load the standard braking system on the front axle. i would recommend that you should fit an upgraded brake kit, also a brake bias valve to stop the back brakes locking on before the fronts. take a look on here, www.rallydesign.co.uk hope this helps regards Dean.

Link to post
Share on other sites
I have a similar setup and to compensate for the lack of a servo I fitted a master cylinder with a smaller bore than the one from the Sierra.This gives a higher pressure for the same pedal force but involves a longer pedal travel.

 

I had the same problem, fitted smaller bore Master cylider from a KA and no more problem, block the extra conection off with a bleed nipple.

 

Mike :rolleyes:

Link to post
Share on other sites
it could also be because the sierra did not origianally have a V8 under its bonnet, all that extra weight on the front of the vehicle will over load the standard braking system on the front axle.

 

I suspect it's a Rover V8 in which case the weight is actually about the same as a Pinto, maybe slightly less. It also might sit further back in the chassis (or not, not 100% on that one).

 

All in this engine fitment will not have a lot of affect on the function of the brakes.

 

Dan :)

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...