This is a repost of a thread put on another forum. Moderators on that forum tend to get upset/delete/ edit anything not LR part number.
This thread finds a home here, Modmin, Dan of this parish - bless him - clearly doesn't fret over such.
There's other makers of these kits. I've seen the Zues version, it's a bit of a lash-up. Me? I run a 109 with Heystee discs all round + 110 MC + servo + pedal-box + prop. valve + RPV et al.
There seems to be a lot of misunderstanding for why you'd fit discs?
Some would have it you'd be fitting discs for more powerful-brakes. Er no. Not quite. They'll try to tell you they can stomp on drums and stop "Just fine". Land rover folklore goes.... all you need is 'Correct adjustment of a time-served design. Thus you don't apply an 'upgrade' to cover poor function parts - you fix them.
Ergo you don't need discs. This is true. Sort of...
Then there's the "I've managed for forty years, and drums were fine in 1968... blah, or there's... "Predict other road-users and drive accordingly; upgrade to late S3 spec" etc. Again... well enough I suppose, yet it's mostly indicative of blinkered thinking. There won't be a real understanding of what discs do.
The next dolt will be along to say "You fit discs because discs don't fade, and LR drums don't fade..."
Ergo you don't need discs. Again, this is true, kinda....
It's true, LR drums don't fade. Least ways they CAN and DO fade - only most of us won't run a LR fast enough, and the rest of us don't live in the Rockies/Swiss Alps, or tow caravans up/down said Rockies/Swiss Alps.
Fact is, stomp harder and drums will reach the limit of the tyres, same as discs. That'd be why discs are not about more stopping power per se. You fit discs for 'feel' and consistency - modern feel brakes. It's this control which gives more stopping-power. And its pleasant 'feel'. See any modern car.
Disc brakes offer a level of control, drums will never match. Done right, discs give a light modern-feel. No more 'ON or OFF stomping'. Like a pre-ABS 110. Suited to anyone doing miles. Discs give a light progressive consistent feel. Thus better brakes for shorter stop-distances. Not more powerful. Grasp the difference.
You want discs for a daily-driver on wet February roads. They stay 'right'. There's no hub-seals or screwing with shoes. No snail-adjusters continually pulling out of whack. If you do my miles messing with drums every 5-6 weeks gets ridiculous. Don't get this wrong, drums are well enough, quite adequate for show-ground miles, and if that's how you use yours, maybe you're best to leave be.
Discs do give you more powerful brakes, not because they are per se "more powerful". The critical point finds, discs proportion and manage forces better. Greater control is a large part of why modern cars have brakes which 'feel' and stop the way they do.
The stronger argument against discs is the cost benefit vs how much 'used-string' the typical LR owner will pay. Many refuse to drive-the-thing. The poseur cohort features high. Mind, if we do drive-the-thing, discs sit at the top of the list for essential mods.
Servo - or not. Many refuse the fact.
This is also a bone of contention, when you remove force you remove braking. Many still refuse to accept this fact - you are 'forced' (SWIDT?) to consider the loses in force in the form of the self-servo of drums. You WILL require far more than the S3 6" servo. I run a 10" coiler servo.
Because payment in used-string and a CSE grade 3 in Physics is a real thing amongst LR owners, many will argue differently. Removal of force will hobble discs. See any modern car - find the lightest diddy hatchback - see its enormous servo. It's bigger than anything fitted to a Series, and for good reason.
Some of the more disreputable conversion suppliers are vested to not mention the servo. Add in the desire to ignore school-boy physics from your pig-headed LR owner, and no wonder there's contention. Friction is always be proportional to force, NOT area. Repeat...friction is always be proportional to force, NOT area. Find forum brake-threads running 5-6 pages fighting this one fact.
An aside: Wide tyres do NOT grip better because the contact-patch is larger per se. They grip better because the contact-patch is in contact with the road MORE of the time (kinda' like the rucked-up rug effect). That is NOT the same as the standard forum brain-dead saying "The area is larger, and a larger-area grips more"
Heystee will tell you to mimic the Defender servo set-up. And you should. Force must come from somewhere - else you'll swap ponderous drums for ponderous discs.
Ahem, it do be.
With that understood. I'll detail the various kits and differing requirements for 88 vs 109:
The Kits
There's been quite a few kits. Some of them are lash-ups. Along with those I've forgotten, Zues, Torrell, Forbyn/Timm Cooper, Design Developments, and an Aussie outfit make them - or did. There's a new-kid trading as LOF.
To further confuse Rocky Mountain used to sell Heystee's Santana based kits, and Heystee used to be called TIC Console. I've experience of all TIC Console/Heystee product, except the earliest Merc derived version. I like the Heystee kits because they allow stock rims. The Forbyn and LOF kits also appear to allow stock rims. I know the others don't.
Choose a Forbyn LOF or Heystee kit if you can't abide fake rims. If you agree with this sentiment, the disc conversions from Forbyn LOF or Heystee will be your 'thing'. If modulars / 8-spokes/Wolf/ iffy rims are OK for you Zues are well enough.
If you run stock 569203/ 569204 2B 1 Ton deep rims etc. Heystee kits work.
There's a few DIY jobs, mostly attempts to f@rt about to save a tenner. And there's complete mis-information on Heystee disc conversions.
Best explain, Heystee don't quote versions. For the purposes of this thread, the Mk1-4 stuff is my designation, not Heystee's.
THERE IS A QUESTION OVER SUPPLY - READ THIS FOR HISTORICAL CONTEXT / PARTS INFO. THIS BEFORE RELEVANCE TO CURRENT KITS
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The first three Heystee variants (Mk1-3) were via LR Santana in Spain.
Santana fitted discs and developed the S3 to become the Series 3a and Series 4.
The Spanish were always ahead of Solihull in development: Heystee followed whatever Spanish LR Santana supplied at the time.
Exception: When Santana went bust, the last and current Heystee kit went to use LR coiler parts, the calliper carries the same 2 x 48mm dual pistons yet body is larger. It's a coiler item. Details below:
THERE IS A QUESTION OVER SUPPLY THUS READ THIS FOR HISTORICAL CONTEXT / PARTS INFO. THIS BEFORE RELEVANCE TO CURRENT KITS
Mk1: (Allows stock LR series rims) - No swivels required.
Santana Cazarola parts which uses Merc MB100 van callipers. MB100 callipers are as large as Deb*$der callipers, This kit has smaller discs. Santana changed set-up when MB100 went out of production. Heystee kits follow:
Mk2: (Allows stock LR series rims) -
No swivels required. Santana Cazarola 2500 DC, 2500 DL, 3500 DL parts. Santana developed their own 2 x 48mm piston calliper. Santana used 1970s R$%^e R$%^& pistons. They fit. This allows a much larger discs than the MB100 calliper. After their tie-up with Fiat/Iveco this set-up gets use on the later Fiat Ducato/Talbot Express/ Alfa Romeo AR6/ Peugeot J5 /Citroen C25. Same van, different badge. In the UK, heaps survive. Same casting machined 48mm x 38mm piston. As Talbot Express camper vans mostly. All parts available eg: pads by Mintex MDB1205 / MDB2911.
Mk3: (Stock LR series rims require spacers).
No swivels required. Santana went into production with PS10/Massiff variant. Larger PS10/ Massiff spec vented discs. A PS10 is the final Series LR. A Series 4 I suppose. It's a leafer too.
Heystee follows. This variant uses same Fiat Ducato/Talbot Express/ Alfa Romeo AR6/ Peugeot J5 /Citroen C25 based calliper as Mk2. However, with vented discs, hence Heystee kit requires 20mm spacers to fit stock Series rims. You can convert the Mk2 kit to MK3 if you wish. You'll require PS10 discs and calliper carriers. I suppose it's an upgrade, I've tried it. Not really required. Heystee produced it because that'd be what Santana were doing with the PS10 at the time.
Mk4: Allows stock rims - Uses unique swivel casting.
Uses largely stock LR de%^*der parts. Santana went bust. Heystee could not source Mk2/3 parts in reliable production quantities. Heystee forced to develop Mk4.This kit is pricey because to get far larger de%^*der callipers and discs in the space requires complete new swivel-castings etc. It doesn't really offer much over the MK2 kit, however it's existence is understandable. The trick in the Mk2/3 kit is the Santana developed small body calliper. Made the right shape/small enough for the job. The de%^*der calliper was never intended to fit a Series. Without production quantities of the purpose-made Santana calliper (seen in kit Mk2/3), and with stock Series rims desirable, Heystee were forced to Mk4. Hence very pricey. For the first time Heystee make a purpose made rear kit too. Use a stock de%^*der rear calliper.
SUMMARY OF HEYSTEE KITS:
If you are the sort to put rims-various on Series, you do not require Heystee kits. Until you insist on 1500 for a full production-run, the supposed advantage of... LR parts in the Heystee Mk4 with swivels sounds great, and is nice enough, yet in use, over the earlier kits, offers no real advantage. . The MK2/3 kit was developed by Santana for the Santana Cazarola, a Spanish Series 3. The Spanish solution has twin-pot 48mm pistons, as does the de%^*der calliper. The Santana Cazarola calliper body is more compact. Hence allows stock rims. No need for new swivel-casting etc.
Top of the pile or not, there seems to be question over Heystee able to supply? i truly hope they are. Nice stuff, I run their PAS kit too.
I'll cover seal kits, pistons, calliper pins parts, servo blah next post.
THERE IS A QUESTION OVER SUPPLY THUS READ THIS FOR HISTORICAL CONTEXT / PARTS INFO. THIS BEFORE RELEVANCE TO CURRENT KITS
Rust costs more than brake-fluid.
Brake-fluid degrades to acid. I write this minded to the the numerous NLA kits, often on eBay etc. Sourcing parts for some kits at 20 years old etc etc.
Be sure you flush before acid rusts pistons and rips seals. Rebuild kit info to follow.
Mk1
As above it's all Merc MB100 Van. Thus caliper is all Merc. Disc is the oddity, rumour has it Britpart were bringing them in. Santana Freno 173222. Hard to source. Or.. with very minor machining, BMW 316/318 discs go on. H
Santana designed their own calliper for Series use in the Mk2. Next...
Mk2
Developed for Santana Cazarola 2500 DC, 2500 DL, 3500 DL
CALIPER 2 Pot (48mm x 2):
Santana Cazorola Freno 173209 &173210 similar to Ducato Talbot; Peugeot J5; Citroen C25; Alfa Romeo AR6.
Calliper can be had from the Fiat derived vans - fit but not quite the same (Pistons = 1 x 48mm + 1 x 38mm) . Easier to flush before the acid rusts the pistons etc, and rips seals.
Caution: Some late PS10 callipers look the same, yet won't take the deep STC1918 RangeRover type piston. The Ps-10 caliper (BET1749 equivalent to PS805040 0) will fit however takes a shorter piston. This means you'll not be able to run your pads down - yes... you could, would think there's greater risk of piston-twist with the lack of depth. I'll say this a few times, easier to look after your fluid.
Pads:
Mintex MDB1205 Fiat Ducato/ Citroen C25. Do not use Mintex MDB2911 Santana PS10 unless using Mk3 kit vented discs. Why? Your calipers are too precious, as above there's risk of piston-twist. I don't run pads over half way for this reason. New pads are cheap insrurance. Fluid is cheap, wrecked calipers will see you cry in your beer.
Put these searches into eBay:
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(MDP287, MDB1205, DP425, P23022, GDB695, BV287, PAD384, BBP1082, BBP1130) (citroen, talbot, alfa, fiat, peugeot) brake pads
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(BP708, P23022, LP378, CVP047, PCP1686, FDB287, FSL287, FVR287, QH2308, BP326) (citroen, talbot, alfa, fiat, peugeot) brake pads
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Rebuild kit
Brake-fluid goes acidic, if you don't flush, you'll need to rebuild.
AutoFren D4031
AutoFren Seals kit for one caliper consists of:
48mm Gaiter / Boot B4176 x 2 (54 x 36.5 x 11mm)
48mm Seal / Gasket B6152 x 2 (54.3 x 48.4 x 3.2mm)
Slider Pin Boot x 2 B5051 or Mintex MBA1301A (11 x 15.9 x 24)
Slider Pins:
Bremtech BCF1309 /Autofren D7127C/ ROVER BAU5642/FRENKIT 812007
Caliper Pistons 48 x 53.6mm:
STC1918 RangeRover Mk2/Citroen C25 Piston 234810; AUTOFREN SEINSA D025226; BUDWEG 234810
Disc: ,
Brembo_08.7223.10; Santana 173214. Getting pricey.
Metrocab DSK2470 can be machined:
FERODO DDF 488
MINTEX MDC823T
DELPHI BG 2902
PAGID 54710PRO
TEXTAR 92171003
NATIONAL NBD485
Apec DSK2470
METROCAB C81032
Volvo XC40 REAR can be machined.
Britpart PS-850238 can be machined - a bit thin, change pads at half-way.
It's possible to make a Mk2 into a Mk3. Requires a PS10 caliper carrier and PS10 disc-swap.
Mk3 next...
Mk3
Broadly the same kit. Sold by Heystee as Santana moved to the PS10. Same rebuild kit.
Discs
Wider vent type disc. Available via Britpart:
Santana Anibal PS10 PS-850237
Pads
Mintex MDB2911 are unique to PS10 - less friction material.
Calliper
As cautioned above, I've seen some PS10 calipers not take the deep piston seen in Mk2 kits.
Mk2 kits can be made to into Mk3 with PS10 calliper carriers & Ps10 discs. Will require 25mm spacers to take stock rims.
Piston;
48 x 50mm - NISSAN MICRA K11
Kits Mk1-3 will fit on the rear too. And were sold as such. I had this set-up for a while, sold as suitable by Chris Perfect / Rocky Mountain back when. This is not advisable. No amount of prop. valves G-valves etc etc will make this work well. Heystee now make a proper deb%&6er based rear kit for this.
INFO FOR ALL DRUM TO DISC CONVERSIONS
With so much mis-information surrounding disc kits, some of the less thoughtful proponents will claim a servo is not required.
It is.
Of course it is, you'll not see factory disc set-ups without appreciably larger servos than anything seen on S3s with drums. Yes, stomping on a pedal produces the same effect. Only as we came in, confusion abounds. You have ON or OFF brakes with no feel. Modern cars are mostly vastly over-servo'ed, this because ABS is used to rein the forces in.
Leading-shoe effect removed, you will need a large coiler servo, and probably proportioning measures too. I run a 109, it needs a prop. valve.
The 88
They're less 'planted'. An 88 with less to hold the rear down, wants more proportion control, not less. Braking will want to up-end an 88 more than a 109. On late coilers there's a different G-valve, 90 or 110. On my 109, I've mimicked the 110 set-up.
My 109...
I run a mid 90s gayer servo + Prop. valve by Wilwood. You don't require braided hoses. Rolls Royce to Lamborghini to Lada, you'll not see a braided-hose on any production car. Real engineers - rather than a bloke with a box of spanners - in the R&D of major manufacturers won't spec. such shonk. Braided hoses are sold by the after-market because... performance. It'd be a whole other thread (mostly centred on keeping manufacturers out of court) yet there's reasons the natural home for braided-hose and fart-can exhausts remains McDonald's car-park.