Massive 109 six cylinder brakes on my 88

[Snagger]

Discs are better, no argument about that; I wouldn't have bothered with my conversion if they weren't, but they don't decrease braking distance, they're just easier to use and maintain.  So, it just begs the question are they £3000 better (the rough cost of conversion kits to do both axles)?  I'd suggest "no".  But as part of an axle swap for several benefits including steering lock, elimination of steering kick back in 4wd and lateral stability, all costing a few hundred pounds, then "yes".

[Bandog]

Never denied this about disks??? My last landy was a six cylinder. It was as fast as a 2cv and couldn't pass a petrol pump!

The military bumpers on mine are included in carrying much more weight. Too much to list. The power steering reduces the kick back you talk about. And it increases weight, so does my spare wheel carrier, dog guard, sound deadening etc etc

This 88 is a heap heavier than standard, including the very heavy detroit trutrack, and Salisbury axle. 

I just recon your theory is a theory, negligible noticeably snagger. It's getting rather silly now. No disrespect 

[Ozzy50]

I'm heavily involved in stockcar racing, mostly F1 , and no one would ever dream of using drum brakes ,not powerful enough,too heavy , too much brake fade and too fragile . Bigger discs do lead to better stopping power that's a fact ,a 1400kg stockcar with plain discs and 2 pot calipers won't stop when hit from around 60 mph into the corner,swap those discs for larger ones and 4 pots and it will,make the discs vented and they won't fade (as badly)either . A well maintained set of drum brakes can be a good set up but they are definitely inferior to disk brakes .

[Bandog]

14 minutes ago, Ozzy50 said:

I'm heavily involved in stockcar racing, mostly F1 , and no one would ever dream of using drum brakes ,not powerful enough,too heavy , too much brake fade and too fragile . Bigger discs do lead to better stopping power that's a fact ,a 1400kg stockcar with plain discs and 2 pot calipers won't stop when hit from around 60 mph into the corner,swap those discs for larger ones and 4 pots and it will,make the discs vented and they won't fade (as badly)either . A well maintained set of drum brakes can be a good set up but they are definitely inferior to disk brakes .

I agree. Never disputed the benefits of disks. Billions of research and development dollars proves this. F1 wrc etc. My point was that the brakes on mine are plenty good enough. 

My friends series has a 200 tdi conversion. He also carries lots of extra weight. The brakes are standard drums, and are adequate, apart from one time I had them fading from a hundred miles per hour, down to about 40. The pedal was lost then. My brakes are stronger,  I ain't gonna lose sleep 

[Ozzy50]

Your 109 brakes will definitely be a big improvement over the standard 88 brakes without a doubt ??

[daslandroverman]

If one looks into the physics behind how brakes work then the benefits of larger drums, discs etc become clearer.

Firstly we need to look at the first law of thermodynamics, that being 'Energy is always Conserved'.

Basically all the energy that goes in, comes out again in one form or another. 

In the case of the motor car it's a large amount of chemical energy in the fuel which is turned into kinetic and heat energy by the engine. 

When it comes to braking you've got a large amount of kinetic energy in terms of the momentum of the vehicle, and the job of the brakes (discounting assistance from things like driveline losses) is to convert that energy into something else.

Top of the class those of you who said heat. 

Brakes generate heat by rubbing the friction material against the rotor be it drum or disc. This heat is then lost into the atmosphere as radiated heat. On technicality it warms the air around it rather than the air cooling it. 

The efficiency of a brake is determined by how well it can dissipate the heat it generates. The condition known as brake fade is due to the brake rotor retaining enough heat that it can no longer effectively convert kinetic energy into heat. 

Larger brakes will have more capacity to be heated up than smaller ones whilst, as already noted, Discs are more efficient/consistent as they dissipate heat much better than a drum setup.

It doesn't surprise me to hear of being able to lock up 10 inch SLS drum setups as drums have a larger surface area of friction material in contact with the rotor, and the shoes have a self servo effect on them also. 

Worth remembering that a locked wheel is converting kinetic energy into heat energy, just using the medium of your tyre and the road. 

A bit of an impromptu physics lesson, but hopefully it's been a little enlightening?

[tacr2man]

An 88 with the full 1ton (Stage 1 V8) brake setup  2ls 3" front shoes ,rears were 11inch sls ,  is more than adequate for repeat stops when towing at max  powered by a RV8 , as I did a 2a rebuild in late 70s with all new brake parts to that spec , in dry very powerful stopping  , (hyd winch and spare tyre on front , gave plenty of front axle weight) in wet too much , had to be really gentle . IIRC  disc  conversion wasnt an option back then .

[Snagger]

21 hours ago, tacr2man said:

An 88 with the full 1ton (Stage 1 V8) brake setup  2ls 3" front shoes ,rears were 11inch sls ,  is more than adequate for repeat stops when towing at max  powered by a RV8 , as I did a 2a rebuild in late 70s with all new brake parts to that spec , in dry very powerful stopping  , (hyd winch and spare tyre on front , gave plenty of front axle weight) in wet too much , had to be really gentle . IIRC  disc  conversion wasnt an option back then .

That's exactly my point.

[Ozzy50]

I can honestly say I have never been in a situation where I thought I had too much brake , disco's landy's and rrc, jap pick ups, wagon's , tractors ,off roading,racing stockcars , never ever had that experience.!

[muddy]

On 26/02/2017 at 5:23 PM, Ozzy50 said:

I can honestly say I have never been in a situation where I thought I had too much brake , disco's landy's and rrc, jap pick ups, wagon's , tractors ,off roading,racing stockcars , never ever had that experience.!

Have you tried a John Deere telehandler? Savage, I've seen a lad end up sat on the dash

 

will.

[WesBrooks]

Too much braking sounds like bad set up to me, or only just swapped in from driving a vehicle with much less assistance.

The perceived rate of braking vs foot pressure is the result of a balance mechanical advantage and servo assistance. Move the pushrod for the master cylinder closer to the brake pedal pivot will increase pedal travel, but reduce required foot pressure. Increasing servo assistance will drop required foot pressure without significantly changing travel. Reducing the master cylinder piston surface area and/or increasing the total area of slave cylinders will have the same effect as moving the master cylinder pushrod toward the brake pedal pivot. Pedal travel can also be increased by over flexible hoses, trapped air, or moisture in the brake fluid.

So, quite a scope for home builders to end up with something they think is over or under braked, just by getting the ratios wrong.

There is also the intended vehicle weight. As people have said you are limited by the tyres grip on the road. More weight means more grip, which means the braking force generated by the pads acting on the discs/drums can be increased. As your vehicle is heavier you'll probably stop in a similar distance, but take that braking system and apply to a lighter vehicle and they'll tend to lock up easier.

What's my point? Notice no mention of discs or drums above? A lot of what is being debated here has little to do with drum verses discs and more to do with the design of the whole system including the suspension/vehicle dynamics under braking, tyres, weight, and driving style.

Brakes system design (inc brake balance) is a complex subject and to draw conclusions from Joe Bloggs who switched from drums to discs or visa versa isn't easy either. Unless the whole braking system had been lifted from a near identical vehicle then achieving a balanced system with good feel would be more luck than judgement unless they put significant effort in.

Would you notice the swap from good drum system to good discs? If driving like the a typical Mrs Daisy then probably not. If you are in competition, drive fast with frequent stops, tow heavy loads, or change your own pads the yes. Will you stop quicker? I predict on average yes because discs are more predictable and consistent. They also shed heat faster keeping away from brake fade for longer on stop from speed or frequent stops.

Would it be worth it financially? Erm, what cars are we here for? Those eastern imports are good value aren't they? ;-) Unless you want discs, or are fortunate enough to fall on the whole system cheap then probably not.

Slight foot note, there is a good chance that Land Rover did size components so that they could use the same master cylinder for drums and discs where there was an option for both on the same model. Doesn't necessarily mean the brake feel will be to your liking though.

[WesBrooks]

Going back to the original post is there enough movement on the master cylinder to be able to get the slaves to push the backing plates of the pads right onto the drums? Might be worth checking unless the master cylinder is a common part or was swapped at the same time.

[Bandog]

La Ferrari, lightest, most powerful ever made, enormous brakes. 

I had a Kawasaki KR 1s 250 once. Same brakes as a zzr 1100, exactly the same brakes. Savage yes, too much, no. 

It's odd how some intelligent people take things so literally. Held back by theory and pseudo logic. Like the man I want to punch the most, Professor Brian cock. 

The reference to enduro brakes was in the realms of hyper advanced motoring. If you can control a front wheel lock up on a dirt bike, a crabby old 4x4 is a cake walk. Like I said, if I really have difficulty, I will book a driving lesson with BSM! 

[Snagger]

On 03/03/2017 at 5:49 PM, Bandog said:

It's odd how some intelligent people take things so literally. Held back by theory and pseudo logic. Like the man I want to punch the most, Professor Brian cock. 

 

It's also odd how some people with so little technical knowledge that need to ask questions that have blindingly obvious answers refuse to accept the well explained and justified comments and the testaments of those who have direct experience of the matter in hand because it doesn't match what they want to hear.  Worse than the fact that these types can't be saved from themselves is their tendency to then insult those that have tried to help them.

[Bandog]

Nonsense 

[Snagger]

I don't suppose it occurred to you that the Ferrari suspension affects the braking, and that it has ABS and probably operates its brakes at a very different pressure to other disc braked vehicles of similar weight?  Is size your only measure?

[Bandog]

It is with my weaner

[Bandog]

30 minutes ago, Snagger said:

I don't suppose it occurred to you that the Ferrari suspension affects the braking, and that it has ABS and probably operates its brakes at a very different pressure to other disc braked vehicles of similar weight?  Is size your only measure?

If you understand the behaviour of the part of the human brain called the "R complex"  you can begin to see why this thread had got really very silly. 

[lo-fi]

Snagger, your posts are usually interesting and informative, if a little blunt, but I have to admit you're being rather dogmatic here. Disks are better. Yeah, OK. Thousands of pounds better? Maybe not. Glad we can all at least agree on that one. 

Your size comparison doesn't really stand up, though (pun intended, let's lighten the mood). The 6 pot drums are a meager 1" larger diameter. That's a whole half inch extra turning moment. Hardly going to set wheels locking up left, right and center with there merest hint of hitting the pedal, is it? They are wider. Which on drums means more leading edge, so more braking effort for a given pedal pressure and a bit more area to distribute and dissipate heat. Great! You might not have to use both feet on that giant brake pedal... Now you can harp on about the theory as much as you like, but from someone that's actually running that setup, I can tell you it works very well. Did the move from 10" to 11" ruin the braking "feel" of the late 88? No. Frankly any of the non servo systems feel b***** awful anyway. For those of us not intent on turning a series into a defender, this is a useful option. 

[Bandog]

True, there are things that I really like about defender, and things I really like about series. And vice versa. 

There becomes a cut off point though, of cutting diminishing returns. 

Of course tax exemption is a plus, but a series is not as good as a defender. 

I do like the old manual 4 wd though. As any 4x4 throughout the world, it's a on road compromise paradox. Most vehicles spend the best part of the time on road. I like the fact that the series is a 2wd until needed. The 88 is pitifully small, with no storage/stowage space. 

You can't even get a mountain bike in the back without taking the wheels off! 

Tackled up fishing rods forget it! 

Poor leg room, poor back room, carp visibility. Marmite. 

Something about them is so comforting and endearing though. I would be justifiably cross and defensive if I had spent so much money on a paradox too, oops I have 

[Hybrid_From_Hell]

being watched 

[Bowie69]

Nice bump nige, this went dead on the 7th.

I reported one of the posts at the time... Didn't hear anything back, but appreciate you chaps are busy.