Series 2 Zeus front disc brake conversion

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Hi,
If i was looking to buy a classic,t&t exempt land rover like ours to drive for pleasure the brake upgrade would be a definate plus,the lack of servicing another,i am sure that you have increased the value by much more than the price of the parts,on mine the overall condition and location of the vehicle did not warrant the expense but for modern road use your system is what is needed,
atb
R
 
Hi,
If i was looking to buy a classic,t&t exempt land rover like ours to drive for pleasure the brake upgrade would be a definate plus,the lack of servicing another,i am sure that you have increased the value by much more than the price of the parts,on mine the overall condition and location of the vehicle did not warrant the expense but for modern road use your system is what is needed,
atb
R
Yeah;)
 
Hi, I’m thinking of changing my 200tdi series 3 to discs and was wondering can you get away with running the standard 16inch wheels or do you have to change them, this would be for the Zeus kit. I need new tires so was wondering wether I would need to change the wheels at the same time.
Thanks,
Edward.
 
No chance they'll fit standard rims. The caliper is in the same space as the wheel well.
Wolf, or modular.
 
Zues are very clear that STD wheels don't fit. Having recently changed from STD LWB rims to Wolfs I can see why. Its not the rim width its the shape of the wheel dish. The STD wheels are desinged to fit around a drum not clear a caliper. The Wolfs are much flatter. Your choice is modulars or Wolfs, modulars are much cheaper 2nd hand.
 
Zues are very clear that STD wheels don't fit. Having recently changed from STD LWB rims to Wolfs I can see why. Its not the rim width its the shape of the wheel dish. The STD wheels are desinged to fit around a drum not clear a caliper. The Wolfs are much flatter. Your choice is modulars or Wolfs, modulars are much cheaper 2nd hand.
Sure I need new tires as well so I will probably buy new just need to find some cheap enough. I will probably go for modulars as I prefer the look.
 
Hi all, sorry to drag this thread out of the depths from last year.

To those of you who have fitted this kit - where is the brake fluid line input to the caliper in relation to the bleed nipple and wheel in terms of clearance?

Secondly - what master cylinder did you use for disc brakes front and drums rear? I have a LWB S2a, running a defender pedal box and servo with a series master currently.

My kit arrives in the next week or two (3 week lead time) and I'm intending to fit braided lines from the chassis rail straight to the caliper.

I will run the line looped around the same way as it does on the military spec from chassis to swivel top but instead of terminating there and connecting back to hard line on the swivel, planning on just using that bracket location as a place to clip the line into place, and then carry onto the caliper and meet it with a 90 degree fitting or banjo.

Why bother? So that i can remove the caliper with 2 bolts and hang it out of the way to do any sort of remedial works to the brakes or hub assembly and not have to add brake bleeding to most hub tasks. Also good to move away from rubber lines as they seem to turn the fluid a shade of black in just over a year.

From my research so far this line will be approx 625mm long, with 3/8 UNF x 24 TPI bulkhead male at the top - with probably a 3/8 banjo and 3/8 UNF x 24TPI banjo bolt - and a rubber sleeve half way down for clipping it to the top of the swivel. HEL supply custom lines like this.

Any comments or pictures of your calipers fluid inputs appreciated. Doesn't seem very easy getting this sort of info from Zeus.
 
Both.png
In Grey  Series  12-10-17 03.png
APV Wilwood Brake proportioning Valve 31-05-18  01.png


If you're unhappy with the doubtful rim choices, Zeus push on you, you're not alone. There's Heystee kits, these kits will take stock rims or even FC/One ton 569204/ 569203 if you've got those.

I'm fitted discs to mine, front and rear. On a 109 I used a Defender pedal-box/Servo with a proportioning valve by Wilwood. I'd think those of you 'lacking-length' will truly need the Wilwood. That missing 21" means, you've less to stop the up-end effect, and/or too much force will go rearward. An 88 is less stable and under braking, goes 'squirelly' quicker, thus you'll more to get spot-on. Either way, to get it 'right' you'll need to fine-tune, and that'll be where a Wilwood comes in. It doesn't need to be a Wilwood, that same valve seems to come up under various brands. If you've drums on the rear, it'd be wise to get a Residual Valve on the drums... no LR MC has one, and they should. Semi auto-adjusts without falling back to the snails which is good.
 
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If you're unhappy with the doubtful rim choices, Zeus push on you, you're not alone. There's Heystee kits, these kits will take stock rims or even FC/One ton 569204/ 569203 if you've got those.

I'm fitted discs to mine, front and rear. On a 109 I used a Defender pedal-box/Servo with a proportioning valve by Wilwood. I'd think those of you 'lacking-length' will truly need the Wilwood. That missing 21" means, you've less to stop the up-end effect, and/or too much force will go rearward. An 88 is less stable and under braking, goes 'squirelly' quicker, thus you'll more to get spot-on. Either way, to get it 'right' you'll need to fine-tune, and that'll be where a Wilwood comes in. It doesn't need to be a Wilwood, that same valve seems to come up under various brands. If you've drums on the rear, it'd be wise to get a Residual Valve on the drums... no LR MC has one, and they should. Semi auto-adjusts without falling back to the snails which is good.

Thanks for the response, good to hear that the proportioning valve is needed for dual discs, I was on the fence about ordering one, do you think they are needed for drums in the rear or just dual disc conversions? Ive had them on cars before so familiar with operation and install.

Master Cylinder: Heystee list the BR 3225A(NRC9529A) or another forum mentioned BR 3235(NRC8690) both are for early defenders with drums and discs - which do you use for discs all round? Any suggestions for which model for disc/drum set up?
https://www.bearmach.com/product/wheel-cylinders-brbhbhwc/brake-master-cylinder-br-3225a/BR 3225A
or
https://www.island-4x4.co.uk/master-cylinder-8391-ferodo-nrc8690g-p-25051.html

Rear Brakes: I am keeping drums on the rear for the time being – long term it would be good to have discs on the rear. Maybe this kit will help a good rear brake set up.
https://lofclutches.com/shop/brakes/brake-kits/series-2a-3-10-rear-brake-kit-1971-85/

Residual Valves: Interesting what you say about Residual Valve’s, I havn’t used them before. Would you suggest one per side or one for the whole rear circuit? I was of the understanding that the snail adjusters brought the shoes close to the drum but with enough not to drag – wont a Residual Valve cause the brakes to drag? Wilwood seem to think 2psi for discs or 10psi for drums. Another thought is that even the best of these wheel cylinders like to leak, I wonder if residual pressure will make that even worse…
https://www.demon-tweeks.com/uk/wilwood-residual-pressure-valve-499824/

Wheels/Heystee: I was originally a bit dubious about not having the series wheel rims any more but having had modulars on for the last 3 or 4 months I'm used to the look now, and the fact they are tubeless and wider, its function over form in this department for me. The heystee kit just adds up too quickly and using branded parts comes in circa £1500 so I went for Zeus.

Braided Lines: I managed to get through to Zeus today and they said that the caliper isn't suitable for a banjo so i've ordered braided lines from HEL with a 90 degree swivel 3/8" UNF 24tpi for the caliper and the same thread bulkhead male at the chassis end, 630mm total length. Rear is same as stock plus 3 inches to allow for future travel mods.


Andy
 
Thanks for the response, good to hear that the proportioning valve is needed for dual discs, I was on the fence about ordering one, do you think they are needed for drums in the rear or just dual disc conversions? Ive had them on cars before so familiar with operation and install.

Both, you'll not see bias correct without. Bias is as important as force increase, there is little point putting more force where it can't be used, not only does this rob somewhere else, it mis-directs what you do have. This will likely create a 'squirrelly' mess on the first wet road. Maximum braking is made impossible. The rear must grab first, to keep you straight. With the right amount of force - if bias is wrong, you'll twist or pull, or simply not stop as well as you could. The OP makes no mention of any of this, we must conclude it can't be 'right'. Load, speed etc are infinite variables, a prop. valve allows the best balance compromise.

Master Cylinder: Heystee list the BR 3225A(NRC9529A) or another forum mentioned BR 3235(NRC8690) both are for early defenders with drums and discs - which do you use for discs all round? Any suggestions for which model for disc/drum set up?
https://www.bearmach.com/product/wheel-cylinders-brbhbhwc/brake-master-cylinder-br-3225a/BR 3225A
or
https://www.island-4x4.co.uk/master-cylinder-8391-ferodo-nrc8690g-p-25051.html

I’ve run both of these, oddly NRC8690 at present (Yes I know, this a rear drum MC?), however the difference is in the bias, see above re: proportioning valve. If you adjust bias... and In the case of the g*ybenders, they’ve a G valve anyway - you’ll never get one of those, Attempts to mimic factory set-up is fruitless. Concentrate on bias as above. You're setting bias, rather than being relaint on the broad preset via the MC, thus your MC choice is less relevant.

Residual Valves: Interesting what you say about Residual Valve’s
….

RPV.: The theory goes that you put one close to the MC, in practice, you’ll need two, one near each drum, far from best but…. the springs are so damned heavy on Series they’ll defeat one 10lb RPV. Three would be good. One each drum, one by the MC, but gets silly. Reading many brake threads, including this one, it's clear the bulk don't understand them, which is worrying.

Wheels/Heystee: I was originally a bit dubious about not having the series wheel rims any more but having had modulars on for the last 3 or 4 months I'm used to the look now.
'spose, depends on how you like your filth? You've said it for 3-4 months, and convinced yourself... Tis' a slippery slope, the 'I-was-never-confused-hat' ( you know the one), umpteen jerry cans, and sink-estate snorkel are next;)

Tis' written, The Gospel.

The Gospel according to St. Phillip of Sterndale.
https://www.900club.org/viewtopic.php?f=7&t=1459&p=9853#p9853

Braided lines…

‘Braided hose gives a firmer pedal’... it's just about the most successful self-perpetuating boy-racer myth, and the car-accessory trade loves ‘em. Harmless I suppose, we're at the point where anyone selling a brake-kit must supply. It’s a subject for a whole other thread….

In short, production-cars costing £3-4 million have rubber hoses, and for sound reasons. There are few applications where rubber is not preferable. The world's manufacturer's could fit braided. If it were really as simple. They don't.

Big bore zhorst et al,.... 'more petril innit?". 150mpg from special carbs, and aliens live under the sea. We really should start a boy-racer myth thread.

And careful those rims don't change your walk? Ahem, if one hand ever wanders to your swingin' hips, you've only yourself to blame.
 
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>>The rear must grab first, to keep you straight

This is dangerous advice.

Rear axle locking must be avoided at all costs - so, the braking on the rear axle must, even in the worst case conditions, be reduced to make sure that the front axle locks first.

Rear axle locking will result in a loss of control of the vehicle, with the rear axle overtaking the front axle very quickly; often so quickly that the driver cannot react (especially in an emergency braking situation!)

Section 3 of the relevant vehicle design legislation, UN ECE R13 describes this in terms of adhesion utilisation, but, the practical interpretation of adhesion utilisation is that rear axle locking must be avoided, and manufacturers must demonstrate this in order to obtain type approval.
 
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>>The rear must grab first, to keep you straight

This is dangerous advice.

Rear axle locking must be avoided at all costs - so, the braking on the rear axle must, even in the worst case conditions, be reduced to make sure that the front axle locks first.....

I wrote: Reading many brake threads, including this one, it's clear the bulk don't understand them, which is worrying. And that's it right there^^^.

With words not written or implied. TR, went off on a tangent,. Better he understands my EXACT words, and reads those again. Correctly set-up, the rear will time to grab/apply first, however, which axle locks first... is about bias. There is a substantial difference. That TR is unable to see the difference between timing and bias, or why this timing is required, is worrying. It sailed over his head. Made worse by having had it part-explained and still not getting it.

Again, we align the vehicle by application of the pressure to the rear circuit first, ahem... milliseconds later, both axles are braked, the bulk of the forces are put the front. We will try not to lock-up, but if anything does lock-up, it should be the front. Thus, we 'time' the rear to 'grab' first, we bias the front to take the greatest force, and if something does lock-up, it won't be the back. It won't be the back, because we read and we understand brakes. We understand why it's desirable for rear brakes to grab/be applied/timed to operate first. //Patronising off.


Rear first.png


If you are wondering how the rear is timed to apply first, here is a X-section of a typical twin-circuit MC. In order for pressure to build in the pipe furthest from the pedal/push-rod, pressure in the circuit nearest the pedal/push-rod must build first. Can you guess which circuit is which? And which circuit grabs/applies first?

Answer: That might depend on which of those springs is stronger, which in turn is a factor in setting bias as well. We can be sure the timings will differ. This is why it can't be always be taken for granted, 'the rearmost pipe is intended for the rear circuit'. On one LR master-cylinder in particular it isn't. Herein is the root to the bias and timing pre-set by the MC. Because in the case of a Zues disc-conversions, we can't use the factory front/rear bias pre-set by the MC - [you'll start ot understand why about now] we use a prop. valve to get as best we can. A very sound reason to use the Heystee kit is... if we can find a factory G-valve, great. that'd help. Only we're forgetting a Zeus kit for one will require a different bias match to the factory/Heystee kit, thus the factory G-valve won't be ideal. To get the correct bias, and timing via the MC, the Zeus kit forces a prop.valve.

If there's one thing we all need to understand on our vehicles it's brakes.

Tall Ratbag
3/10 See me.
 
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Many years ago when I first learned to ride a motorbike I was taught to apply the front brake first. This was so weight transfer to the front wheel took place before you applied the rear brake and prevent locking rear wheel.
 
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