Steve W Posted October 10, 2001 Share Posted October 10, 2001 Well not really a tech question more a request for some advice. The car is a 90 supersprint now fitted with a 2l Zetec. I use it mainly on the road but I'm starting to do more trackdays. After an airfield day at Bentwaters I really noticed that the brakes could do with some work. The rear pads and disc's are now shot so just the excuse I need for an upgrade. So I've had a chat to a few people and have been suggested the following. Willwood four pot callipers at the front with new vented grooved disc's. Keep the standard rear callipers, fit new standard solid disc's. Green stuff pads front and rear. I'm getting some prices together at the moment but is there anyone out there with experience of this set-up ? The Willwood callipers are a little cheaper then the AP ones but are the AP worth the extra cost ? Edited by - steve w on 10 Oct 2001 12:44:46 Link to comment Share on other sites More sharing options...
philwaters Posted October 10, 2001 Share Posted October 10, 2001 Hi Steve, I recently tested a K-series car with the Alcon brake system and was very impressed. It didn't have the same feel to the AP set that were on another (VX car) but they certainly stopped the car well. The AP's had a lot stiffer pedal, but I now think this is down to the master cylinder. I more recently (Friday) went to Cadwell and passengered in both cars, two sessions in each, and there wasn't a lot in the bracking. The AP's had the edge for bracking hard and late, but then it had A021R's and the other car had A539's (not as sticky). I think the Alcons are at least worth looking at (James Whiting sells them - see www.jameswhiting.co.uk under performance parts). I will be getting these next year after my 2lt Zetec goes in this winter. I have also seen the Willwood ones and they look good - but don't know of anyone with these fitted. (p.s. any comment on my cooling thread) Phil Waters "Darling, DO you love the 7 more than me?" "Driving OR Fixing?" Caterham on the brain, Caterham around the body! wink.gif Link to comment Share on other sites More sharing options...
gordon wilson Posted October 10, 2001 Share Posted October 10, 2001 My VX engined car has just been to James Whiting for the Alcon conversion and subsequent Goodwood/Aintree track days confirm a huge improvrement in feel and stopping power. Suggest talking to James, the rational for his preference for this alternative is worh listeneing to. Link to comment Share on other sites More sharing options...
deanteam Posted October 10, 2001 Share Posted October 10, 2001 Gordon, which pads are you using (if it's not a trade secret)? Link to comment Share on other sites More sharing options...
Peter Carmichael Posted October 10, 2001 Share Posted October 10, 2001 Steve, You will continue to wreck the rear brakes because they don't get the cooling airflow that the fronts get. You will probably be better off with a harder pad than green stuff. Trackdays are hard on brakes. Red stuff are a good bet. In Mintex terms, I had 1144 pads crumbling from heat at the rear and had to change to the full metallic 1155. I think Pagids are probably the best (expensive) option around at the moment. Link to comment Share on other sites More sharing options...
Miraz Posted October 10, 2001 Share Posted October 10, 2001 The Pagid pads seem to have a reputation for lasting much, much longer than anything else. If this is the case then it makes the initial expense a little easier to justify. Can anyone confirm/deny this? Miraz Link to comment Share on other sites More sharing options...
Steve W Posted October 10, 2001 Author Share Posted October 10, 2001 Thanks Peter,I think the rear pads gave out in the end as they were running very thin ? Made it fun chasing an R500 in a car with fading brakes and loads of understeer. How about Greens all round for the road and Red's for the track. Anyone with Willwood callipers around or should I look at the Alcon's or pay the extra for the AP ? Are the standard rear callipers fine as most of the braking effort is going to be at the front ? Should I fit vented disc's at the rear to help with the heat and can they fit on the standard calliper ? Edited by - steve w on 10 Oct 2001 16:26:59 Link to comment Share on other sites More sharing options...
Peter Carmichael Posted October 10, 2001 Share Posted October 10, 2001 What a lot of derived questions!! >>How about Greens all round for the road and Red's for the track. Naah. The pads need to bed in to the disks and swapping pads around would encourage the disks to no longer be a perfect match for either set of pads. Reds all the time is quite manageable (I am assured). I run Mintex 1155 all round and this is fine although the brakes have less bite on the road than they used to have. >>Anyone with Willwood callipers around or should I look at the Alcon's or pay the extra for the AP ? Your choice. Put it this way. The APs will work and you won't need to think about them again. >>Are the standard rear callipers fine as most of the braking effort is going to be at the front ? The standard calipers are OK, but the self-adjusting handbrake mechanism can back off the pads between applications (crap Ford design). This can make the brake feel less good than it could be. >>Should I fit vented disc's at the rear to help with the heat and can they fit on the standard calliper ? No they won't fit the standard caliper. I have it on good authority that a bit of ducting sorts out the rear brakes, but I am not about to start cutting experimental holes in my carbon wings. The only vented disk set up for the rear that I know of is Caterham's 2001 Superlight racer spec (no handbrake). This sorts out the rear brakes for good, but really you only need a high temperature pad in the standard calipers to get by. Link to comment Share on other sites More sharing options...
Paul McKenzie Posted October 10, 2001 Share Posted October 10, 2001 Peter is right about green stuff pads and their lack of resistance to high temperatures; I changed to green stuff front pads( I asked for red, but they persuaded me green were best for Caterhams)in the summer ('96 Vauxhall with standard brakes) and did a couple of trackdays and a small amount of road mileage. My initial experience with greens were the same as other people reported i.e. good performance at first which then deteriorated as the pads glazed?, plus very little wear of the pads. A couple of weeks ago, I thought the braking had deteriorated significantly so had a look at the pads - guess what, one pad from each front caliper had a crack right across and completely through the friction area. My conclusion (and the EBC distributor)- green stuff pads are not suitable for standard Caterham discs - they get too hot, and begin to disintegrate. I did put my old Mintex 1144's back in and they were an immediate improvement and I really rate them, however I'm going to try red stuff next, but never again green stuff - IMHO they are not up to the job. Paul Link to comment Share on other sites More sharing options...
gordon wilson Posted October 10, 2001 Share Posted October 10, 2001 deanteam, Green stuff, but I must admit that they smell really hot under serious pressure ie max speed down to 40mph ish in a real hurry, and have not yet had the chance to check them for wear/condition. Link to comment Share on other sites More sharing options...
Jeff Posted October 11, 2001 Share Posted October 11, 2001 Hello Steve: I too have a 1990 2l Zetec. I have uprated to the Wilwood conversion via Rally Design. Upon weighing the calipers I saved a tremendous amount of weight (can't remember exactly) but gained it back with the vented rotors. There was a weight savings, however, not as great as anticipated. The car is used mainly for track days and the brakes are a great improvement. I am currently using green stuff pads. Would I go the same route again? The Willwood kit required machining material off my hubs to gain clearance. My tie rod end boots rubbed the vented rotors. I replaced them with rose joints. If I do it again I would go the Alcon route. I really wonder if our cars really need the vented rotors. I just keep thinking of the extra rotational weight and the effort required the accelerate and turn that weight. Why do we go for lighter wheels? Enjoying my car in the States. Link to comment Share on other sites More sharing options...
Mike Biddle Posted October 11, 2001 Share Posted October 11, 2001 I am also going to upgrade my brakes soon, and was going to make a posting, but since the thread is now running, and with apologies to steve, the alcons look really good except one thing, they don't have dust seals. This may not be too much of a problem in UK but we have lots of fine sand and dust blowing around here and that worries me. Does anybody know how often the alcons require attention? Is there any way to fit dust seals? Link to comment Share on other sites More sharing options...
Fast Westie Posted October 11, 2001 Share Posted October 11, 2001 Steve I have Wilwood calipers on my race Westfie1d with standard Ford rears and a pressure limiter. I have the Wilwood Poly D front pads and was running Mintex M1144 rears. On a short circuit like Lydden I had no brake problems, but at Croix (hard on brakes) I overheated the rears and wore about 2/3 of the pad. I have now fitted Redstuff rears and installed some ducting. I don't think you will need vented fronts, I can't get mine to fade (perhaps I should brake harder!) The car in front is a Westfie1d wink.gif Link to comment Share on other sites More sharing options...
Fast Westie Posted October 11, 2001 Share Posted October 11, 2001 Peter In Mintex terms, I had 1144 pads crumbling from heat at the rear and had to change to the full metallic 1155. Do you find these chew up the disks? The car in front is a Westfie1d wink.gif Link to comment Share on other sites More sharing options...
Peter Carmichael Posted October 11, 2001 Share Posted October 11, 2001 No. The disks are fine after two years running like this. Link to comment Share on other sites More sharing options...
EFA Posted October 11, 2001 Share Posted October 11, 2001 My car has one of the original discs fitted with the big brake upgrade in 1994. This disk shows zero signs of wear. The car has done sprinting and many track days on this disc. The other brake disc was replaced a few years ago when I decided to refit a brake pad metal side to the disc. It was a very late night wheel bearing change that day... I would go for the AP setup. It fits and works a treat. I would go so far as to recommend it all round. I am of the opinion that the two pot rear calipers offer improved cooling over the Sierra item. These are a far more researched and tested option on Sevens that any other setup. Anyway Steve since when have you needed brakes??? Just unscrew the oil filter....has a similar effect! I cannot vouch for Green Stuff on a Seven, but I have Red Stuff on my car. Regular regreasing of the pads with coppaslip is necessary to prevent excessive squeeling, but the actual braking and life of the pads is better than anything else I have tried inc. 1155/1166 Mintexes. Contrary to some opinions Red Stuff do stop well when not warmed up. When hot they stop very quickly. Alex uses Red Stuff on VDU as well, with +ve results. As a sideline I am getting some odd problems with Green Stuff on my Fiat Coupe, but then it does many more (equally thrashed) miles than the Seven and is 2.5 times the weight. I actually think that the Green Stuff problem may be that they cook when you have parked the car after a long thrash. I have some very odd blue heat splodges (not radial) on the Fiat's front discs! Fat Arn The NOW PROVEN R500 Eaterid=red> See the Lotus Seven Club 4 Counties Area Website hereid=green> Link to comment Share on other sites More sharing options...
Steve W Posted October 11, 2001 Author Share Posted October 11, 2001 Arrrh Capt Fat of the fat people good to hear from you. It's taken a while but I've now started to use that thing call the brakes. I'm considering the Alcon set-up as they use the standard lighter discs. As you know I can do with losing as much weight of the car as possible. Please don't talk about the oil filter I still have nightmares about it. Anyway I still made the ferry in time. The now wife's 106 is still in one peace and I seem to remember you were glad of the lift home. It would seem from a few comments that the Green stuff pads my not be up-to taking the heat of a hard trackday. I think I may try the Red one's all round. Link to comment Share on other sites More sharing options...
David Hopkins Posted October 17, 2001 Share Posted October 17, 2001 With respect to the comment from one ill informed individual regarding the self adjust mechanism backing off the pads he is talking rubbish , the truth of the matter is that he has his handbrake cable over adjusted which artificially reduces the design running clearance in the adjuster mechanism . As the pads wear the caliper reverts back to its designed in clearance . Does everyone follow ? My car has AP fronts with std Mcyl , travel is not ideal and most of travel is due to the rears ( pull the Hbrake up one click and see the difference . To over come the fluid consumption issue with the rear brakes you need to fit a trap line pressure valve in the rear line . You need to play around with the pressure to achieve optimum ie take up the clearnce ( caliper threshold )but no drag . This is the right way to do it and will ensure pedal travel remains constant and short providing you adjust the hbrake cable correctly . With respect to vented rears the std caliper will not accomodate vents , this caliper though is from Ford Scorpio and there is a vented version ( identical other than it spans a thicker disc . This caliper was fitted to 24v Scorpio's and Escort Cosworth and should bolt straight on assuming the disc dia that Caterham specify is the same as that used by Ford . Speak to Performance Braking ( John Freeth )01600 713117 about the valves mentioned above . I am about to do this mod to my car . By the way I work for the company that designed and developed these calipers for Ford . Regards Link to comment Share on other sites More sharing options...
Graham Perry Posted October 18, 2001 Share Posted October 18, 2001 Steve W , Your original planned set up looks ok except for the Green stuff at the rear where they will overheat. I have upgraded to Alcons/Greenstuff on the front and even with a balance valve the rears get far hotter than the fronts when measured with my pyrometer. I would suggest if you want Greens at the front that you either fit the strandard Ford pads on the rear (I use the Fords) or the EBC Red Stuff. A cheap balance valve probably wouldn't go amiss either, as they are simple to fit. David Hopkins is right about the handbrake adjuster, you have to be careful not to adjust it too tight or it fails to automaticallt adjust properly. One other thing, try to lay you hands on the correct tools to wind back the brake cylinders on the Ford rear caliper as they have an incredibly fine thread and it will take nearly half an hour (and blisters) to do using just pliers in the cylinder slots if your pads are quite worn. Link to comment Share on other sites More sharing options...
Miraz Posted October 18, 2001 Share Posted October 18, 2001 David, The caterham rear vented disc is AP part number CP3707-107P which is a 254mmx18mm disc. Miraz Link to comment Share on other sites More sharing options...
tony pashley Posted October 18, 2001 Share Posted October 18, 2001 Graham - I seem to be running the same brake set-up as you and I too ran some temp tests too as I may have a curious thing happening with the brakes - possibly sticking piston but not quite sure yet - it only seemed practical to me to take disc temps. I was expecting the rears to be hotter (a same weight, but not same spec, 7 with same brake set-up on the same day met that expectation - ok this ain't science, but maybe gives a vague idea). I was recording nearly double the disc temp at the front, that I reached on the back, even before I decided the handbrake was a wee bit too tight. The actual temp figures meant nothing to me. Do you recall what figs you saw in your experiment? I'll try to find the notes I made on the day... Link to comment Share on other sites More sharing options...
Steve W Posted October 18, 2001 Author Share Posted October 18, 2001 Thanks for your advice everyone. Almost too much info. I've been told that the caterham AP set-up will not fit my 89/90 car, so it looks like it's the Alcon or Willwood for me. I will look at fitting a balance valve at the same time. I think I'll try the Red stuff pads all round and see how I get on. Now just waiting on prices of the Willwood set-up to decide. Edited by - steve w on 18 Oct 2001 10:20:02 Link to comment Share on other sites More sharing options...
Peter Carmichael Posted October 18, 2001 Share Posted October 18, 2001 Glad to be ill-informed for a change... But what is it that you are describing: As the pads wear the caliper reverts back to its designed in clearance . Does everyone follow ? My car has AP fronts with std Mcyl , travel is not ideal and most of travel is due to the rears ( pull the Hbrake up one click and see the difference . To over come the fluid consumption issue with the rear brakes you need to fit a trap line pressure valve in the rear line . You appear to be concurring that the Ford setup, as supplied by Caterham is *crap*. Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted October 18, 2001 Share Posted October 18, 2001 >>the caterham AP set-up will not fit my 89/90 car I've seen cars of this vintage with big brakes. What's the problem? Alex Link to comment Share on other sites More sharing options...
David Hopkins Posted October 18, 2001 Share Posted October 18, 2001 With respect to the rear caliper I wouldn't say it is crap it just wasnt designed for a Caterham . The rear caliper has to have a built in clearance in the adjuster ie the clearance between the nut ( in the piston ) and the threaded part of adjuster , otherwise the caliper would adjust out all the clearance and you would have binding brakes . The AP race cylinder is a larger dia therefore travel is reduced but pedal effort for a given decel will go up . It is expensive though compared to the trap line pressure valve . By overadjusting the hbrake you are artificially closing down the designed running clearance but as the pads wear the adjuster doesnt react until you have exceeded the design clearance . Hence you perceive the caliper has backed off the pads , wrong , they have simply worn . The valve I referred to is not a frt / rr bias valve it is a valve which traps a small amount of residual pressure in the rear line to overcome the issue you complained about . Furthermore if you try and fit the vented rear caliper you need to check you can still get the wheels on as the extra disc thickness and caliper bridge width grows in the outboard direction from memory . The issue of the rear caliper is all about displacement and was designed for a different car , pedal box ratios , driver seat position , pedal height , mcyl dia all affect the issue of pedal feel and travel . If you transplant parts from other cars without due consideration to all the influencing factors you can end up with some of the issues described . Link to comment Share on other sites More sharing options...
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