Jump to content

Zeus rear brake disc conversion


Cornish Rattler

Recommended Posts

9 hours ago, Cornish Rattler said:

For now I'm using the std none servo master cylinder but once the rear disc brake conversion is done I will see how it goes and if needed I will buy a a better master cylinder and servo :)

Wow, no servo on discs, that must take a firm push to get anything happening.

Link to comment
Share on other sites

2 hours ago, Snagger said:

It’s a good test of bulkhead integrity, for certain!

I am still bleeding my brakes (lockdown and remote garage so no access) so it will be interesting as I only have room for a short pedal tower and no servo on RRC brake MC. It may turnout to be too much as LR increased the pedal tower height for the brake pedal but I have to use a LHD clutch pedal for it as it is in a S1 with low bonnet. Actually it is the length of the dual MC that is too long to fit a tall brake tower without modification as it angles the MC down towards the S1 dashboard.

Link to comment
Share on other sites

3 hours ago, Snagger said:

Can you fit a remote servo?

Yes I had one on the single line drum brakes and I have a pair that I was going to fit with the RRC twin cylinder twin line front calipers. Now I have fitted 90 front calipers I don't need twin lines to the front and don't want the rear through a servo particularly. Time will tell (once I can return to it) as if it is too hard I will add a the pair of servos. The Volvo 303 6x6 had them like that.

Link to comment
Share on other sites

  • 2 weeks later...

I run a coiler NRC4772 servo on 4 x Heystee discs. Mine was undriveable without, and the reason is school-boy stuff,. Friction is a factor of force not area. Without a servo to make-up the force deficit now that the self-servo effect of the drums has been removed,  it can't be great. Got to give it to you, you've got balls. Force from the drums now removed, if it's an improvement, what state were the drums in!

 

 

  • Like 1
Link to comment
Share on other sites

On 1/20/2021 at 12:29 AM, Landrover17H said:

I run a coiler NRC4772 servo on 4 x Heystee discs. Mine was undriveable without, and the reason is school-boy stuff,. Friction is a factor of force not area. Without a servo to make-up the force deficit now that the self-servo effect of the drums has been removed,  it can't be great. Got to give it to you, you've got balls. Force from the drums now removed, if it's an improvement, what state were the drums in!

 

 

All drums and brakes was new ish when i replaced them 

Link to comment
Share on other sites

You cannot achieve reasonable braking with disks and a standard LR non-servo system pedal and master.  The callipers need far higher pressure than the drum system, so without some sort of boosting system or a mechanical system that increases leverage or uses a smaller bore, longer travel master, you just won’t get the pressure you need.  It’s just physics, not opinion.

Link to comment
Share on other sites

On 26/01/2021 at 11:35 AM, Snagger said:

You cannot achieve reasonable braking with disks and a standard LR non-servo system pedal and master.  The callipers need far higher pressure than the drum system, so without some sort of boosting system or a mechanical system that increases leverage or uses a smaller bore, longer travel master, you just won’t get the pressure you need.  It’s just physics, not opinion.

Yes i totally agree with that and i do intend on fitting a servo and bigger master cylinder but not decided on which ones to get plus i couldn't afford to buy everything at once so once the rear brakes are done then i will decide which to go for.

  • Like 1
Link to comment
Share on other sites

There is a lot of variation in what people prefer and what will work for different people, of course.  I have driven some cars with such light pedals and so much boosting I thought them dangerous for my size and weight of feet/leg, like the Micra.  I like the feel the whole Discovery 1 system gave my 109, and it feels very well balanced, but some will be content with the SIII master and servo, which would require quite a lot more pedal effort, and some would prefer something lighter.

Link to comment
Share on other sites

I understand the comments, and they are not about my set up specifically but until I get to try my design (RRC system but no servo) at higher speed on private land I can't make a final decision. I used to have a servo on my S1 on drums until it failed, once removed I was back to std brakes but stopping at a motorway junction showed just how much force it required to stop from higher speed!

AFAIK most race cars don't have servos and go a lot faster and stop a lot harder?

 

Link to comment
Share on other sites

8 minutes ago, missingsid said:

 

AFAIK most race cars don't have servos and go a lot faster and stop a lot harder?

 

That is what i was talking about.    it takes a lot less force to push a little piston in to a cilinder that's  pushing a larger piston out of a cilinder.  On my track car i had two masters, a 0.75 for the rear and 6.25 for the front with a bias in the pedal that could be ajusted.  

Link to comment
Share on other sites

16 hours ago, missingsid said:

I understand the comments, and they are not about my set up specifically but until I get to try my design (RRC system but no servo) at higher speed on private land I can't make a final decision. I used to have a servo on my S1 on drums until it failed, once removed I was back to std brakes but stopping at a motorway junction showed just how much force it required to stop from higher speed!

AFAIK most race cars don't have servos and go a lot faster and stop a lot harder?

 

Race cars are also a lot lighter than a Land Rover!

They’ll  have systems that use mechanical advantage like long pedals, long travel, small diameter master cylinders and of course special pads and disks with much higher friction coefficients than we use.

Link to comment
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.
Note: Your post will require moderator approval before it will be visible.

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.

×
×
  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy