Sue Franklin Posted July 11, 2016 Report Share Posted July 11, 2016 Probably being a numpty as usual but those of you who know me know I do not DO technical! One of my members with a Spitfire IV would like to uprate his brakes. I have no idea technically what to tell him (John not here atm to ask) so you guys are bound to know. Can he fit a servo - I guess yes. How etc. Would appreciate help please. Link to comment Share on other sites More sharing options...
KevinR Posted July 11, 2016 Report Share Posted July 11, 2016 First question is why ? If you can lock the wheels with the brakes as they are - and you can with standard brakes - then no amount of uprating will improve them. A servo will only make the pedal lighter to push for a given amount of braking. It won't make them any more efficient. Bigger disc rotors and more pad surface area will just mean you lock up the wheels more easily, so back to the question, why ? Link to comment Share on other sites More sharing options...
Pete Lewis Posted July 11, 2016 Report Share Posted July 11, 2016 Sue if you can gather just what he needs we can make some suggestions pete Link to comment Share on other sites More sharing options...
JohnD Posted July 11, 2016 Report Share Posted July 11, 2016 First question is why ? If you can lock the wheels with the brakes as they are - and you can with standard brakes - then no amount of uprating will improve them. A servo will only make the pedal lighter to push for a given amount of braking. It won't make them any more efficient. Bigger disc rotors and more pad surface area will just mean you lock up the wheels more easily, so back to the question, why ? More pad surface? Shureiy stone mishtake, Kevin, laws of friction 'n all that? More PRESSURE, yes. John Link to comment Share on other sites More sharing options...
Clive Posted July 12, 2016 Report Share Posted July 12, 2016 Bigger brakes do help, observation alone confirms that! The first thing is that spitfire brakes are (or should be) perfectly good if all working correctly. Often the reason for wanting upgrades is worn or poor condition components. Best thing is to find out what the issue is! But a set of new, standard brake discs, wheel bearings correctly set, calipers not sticking, master cylinder working correctly, not old brake fluid and a decent set of pads (mintex 1144) should see it stopping nicely. Obvious upgrade if he is venturing to 100bhp+ is a set of GT6 front brakes/uprights, or as a cheaper and perfectly good alternative, fit GT6 standard discs, and a set of aftermarket "princess" 4 pot calipers. Would need a 0.70 master cylinder too. Link to comment Share on other sites More sharing options...
juppy Posted July 12, 2016 Report Share Posted July 12, 2016 I would also agree with Kevin, and on a recent trip down to the IOW May weekend I proved more than once, that properly set up and functioning brakes on a Spitfire or Herald, or any of our cars for that matter are perfectly adequate. I locked all four wheels on the A43 due to a lapse of concentration and then noticing a van travelling in my lane at about 30mph! The brakes were not the limiting factor, the tyres were, as once you have locked your wheels and are skidding you don't need any more braking!! I think what people percieve as poor brakes is the difference between the sharp feel you get in a modern car and the feel of our brakes rather than their efficiancy. Properly set up, adjusted and quality components are all that you really need for good brakes. However if you want to "upgrade" them there are as suggested above easy well proven routes to go down. The Princess callipers as mentioned are like gold plated rocking horse droppings now, however the Club Shop will shortly be able to offer brand new aluminium 4 pot callipers that fit Spitfires and Heralds with standard wheels. Link to comment Share on other sites More sharing options...
dougbgt6 Posted July 12, 2016 Report Share Posted July 12, 2016 While I don't want to get into AOTHER argument with the "doesn't make it better, just makes it easier" brigade, I have a servo and any Triumph I own after this one WILL have a servo.! I replaced my non working Girling with the superior Lockheed type. The fitting instructions have to be followed exactly. Use all the mounting brackets and get the servo at the right angle, which makes it a bit fiddly to get in the space available, I had to shorten the bolts between servo and back mounting plate. Once fitted it didn't work and because I'd shortened the bolts t didn't think I could return it. So, I stripped it down and fixed it. I suspect it had previously been assembled by a child in China. There was a reason it was £30 cheaper than anywhere else! I would also suggest Mintex 11/44 brake pads, sold by the club shop, a big improvement over standard pads. Don't bother with dimpled and grooved disks, they don't make any difference to normal driving and nobody tells you they are NOISEY! I have a hardly used set if anybody wants them. Link to comment Share on other sites More sharing options...
Sue Franklin Posted July 13, 2016 Author Report Share Posted July 13, 2016 Not for me - older Devon member wants to make braking easier! I think Kevin may have hit the nail on the head - he wants to make the pedal lighter than it is. Link to comment Share on other sites More sharing options...
Pete Lewis Posted July 13, 2016 Report Share Posted July 13, 2016 Then buy a servo kit its easy to fit , they are universal kits and not model dependant, so dont expect any clues in the instructions you get the servo ,a bracket , some pipe and a hose The braking system needs to be in a good condition before you add a servo, search around suppliers , the prices vary a lot £120 to 180 for the same kit so a little homework will pay off Pete Link to comment Share on other sites More sharing options...
JohnD Posted July 13, 2016 Report Share Posted July 13, 2016 An alternative would be to fit a smaller diameter master cylinder. Higher pressure for same foot effort. That's the roundabout - the swings are longer pedal travel. But it's a far easier conversion, and some say that a servo gives less 'feel'. John Link to comment Share on other sites More sharing options...
dougbgt6 Posted July 13, 2016 Report Share Posted July 13, 2016 Pete, my instructions were quite comprehensive, if a little chinesey. John, I tried a smaller 0.70" diameter MC when I thought I had a problem with my 0.75". Certainly a longer travel but I didn't really notice any higher pressure benefit. Link to comment Share on other sites More sharing options...
Pete Lewis Posted July 13, 2016 Report Share Posted July 13, 2016 One old idea is to just make the pedal pad larger , makes a big change to the feel, pedal load pete Link to comment Share on other sites More sharing options...
JohnD Posted July 13, 2016 Report Share Posted July 13, 2016 I'd have gone for smaller. M/cs available with integral reservoir down to 0.625" (5/8") AP make without a reservoir (but you can screw in a plastic one) down to 0.55 (14mm) OK, longer travel but as said, such an easy mod, and less than £20 each, new. JOhn Link to comment Share on other sites More sharing options...
Sue Franklin Posted July 20, 2016 Author Report Share Posted July 20, 2016 Thanks guys - will pass on to my member. Link to comment Share on other sites More sharing options...
grahame walker Posted August 1, 2016 Report Share Posted August 1, 2016 Hi, I am a new member and hove only had my spitfire 1500 for 10 months and would also like to fit a servo to reduce the pedal presure required being used to modern cars. However, I have the tandam braking system fitted and would therefore have to fit the single line master cylinder and do away with the PDWA valve. Have any of you tried this and if so did it work? Thanks in advance for any comments. Grahame Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 1, 2016 Report Share Posted August 1, 2016 maybe have a look at later GT6 as some had servo on just the fronts and some have dual line and PDWA you may run into troubles with MOt if they expect to see dual line and find its been deleted needs some homework before you jump just spotted the universal fits all servo kit on ebay under brake servo classic mini for £92 Pete Link to comment Share on other sites More sharing options...
dougbgt6 Posted August 1, 2016 Report Share Posted August 1, 2016 Before Feb 73 the GT6 servo was an extra, working on all 4 wheels. After Feb 73 the servo worked on the front wheel only. The front wheels only configuration has a larger master cylinder and larger brake slave cylinders on the back. Both the larger single master cylinder and the slave brake cylinders are rare items and you'd be lucky to find them. So probably best to go for the early 4 wheel configuration. Rimmers list a dual master cylinders for both early and late GT6s. As the servo was standard on late GT6s there must be a way to fit the servo on dual brake systems? Thinking about it, maybe this where the front wheels only idea came from? It should be easy to put the servo on the front wheels only part of the dual master cylinder? Link to comment Share on other sites More sharing options...
grahame walker Posted August 1, 2016 Report Share Posted August 1, 2016 Hi Guys, thanks for the prompt replies. I have spoken to a local garage about changing from a tandem system to a single line one, and he said that it would not make any difference so long as it met the minimum requirements when put on the brake roller/tester. However, the hand brake efficiency will have to meet a higher standard as this 'emergency' brake would not also have either the front or rear brakes working if there was a leak in the system. Going down the GT6 method would still require a new master cylinder, so do you think this would be better than just fitting a single line one from the earlier 1500 model? Cheers, Grahame Link to comment Share on other sites More sharing options...
JohnD Posted August 1, 2016 Report Share Posted August 1, 2016 I don't know what he can have meant, "meet a higher standard ... beause it would not have either front or rear systems working.". He's taking nonsense. Refer him to the UK MoT Manual, its online, see section 3.7 page 2 " Testing". The manual consistently refers to the "parking" NOT "emergency" brake, and the test is exclusively of the mechanical system, with no hydraulic assist. Suggest you find another garage with more knowledge of car systems before you entrust safety critical work to them. And further to attend your local Area Group meetings, to learn where such an establishment might be. Or, speak to one of the several specialists who advertise in the Courier. John Link to comment Share on other sites More sharing options...
Casper Posted August 1, 2016 Report Share Posted August 1, 2016 Handbrake (parking brake) requires higher efficiency on single line systems. http://www.motuk.co.uk/manual_3100.htm I assume the logic is that it is more likely that it may be called upon in an emergency, although this is not stated. C. Link to comment Share on other sites More sharing options...
JohnD Posted August 1, 2016 Report Share Posted August 1, 2016 Thank you, Casper, I see what he means now. John Link to comment Share on other sites More sharing options...
dougbgt6 Posted August 1, 2016 Report Share Posted August 1, 2016 None the less, and not with standing, it does appear to me that you CAN attach a servo to a dual braking system. Can anybody shoot me down and tell me why not? Link to comment Share on other sites More sharing options...
Clive Posted August 1, 2016 Report Share Posted August 1, 2016 All modern cars have a serco on the brake master that operates on both circuits. In fact some triumphs (certainly dolomites) used that method. But there is not enough space on a spitfire/gt6. So a servo has to be remote, and can only work on one circuit. That explains why the rear slave cylinder was changed, to try to preserve the front/back brake balance. No reason it would not work on a spitfire too. Link to comment Share on other sites More sharing options...
KevinR Posted August 2, 2016 Report Share Posted August 2, 2016 I see no reason why you cant fit TWO servos with a twin master cylinder - and then drive one circuit from one servo and the other from the second servo. Jonathan Binnington fitted two servos to his car, with each driven from a single master cylinder with a balance bar between them. Link to comment Share on other sites More sharing options...
grahame walker Posted August 3, 2016 Report Share Posted August 3, 2016 Sorry if I've confused things by referring to the hand brake as an 'emergency' brake, but I was only repeating what I was told. I will try to attend the local club meetings only I'm still getting the car ready. Replacing the drive shaft oil seals at the moment. Thanks again for the feed back. Grahame Link to comment Share on other sites More sharing options...
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