Hi, I'd appreciate some feedback from the forum users in regard to the best front brake calipers to use - must be V.A.G. parts bin not aftermarket - for a 280 mm conversion on a Mk1. Currently my car runs 280 mm discs and the original calipers fitted to adapter brackets mounted to the original hubs. Although quite a lot better than standard, I feel that more could be gained from a caliper upgrade too. Any advice / feedback appreciated !. Kind regards, John.
Some Audis (s2 I think) had 4 pots on 280ish discs. Your current brackets should fit, I think. EDIT: Assume as you're already running adaptor brackets, that they're allowed. Are you really struggling for brakes with 280s on a mk1? My Rocco runs 280s and rear discs. Too much braking, if anything.
I run the G60 calipers with 280mm discs using the adaptors on the cabby, rear disc conversion and 9" servo with 24mm m/c good discs and pads are key, makes the car stop like any modern car. Though my personal opinion on the adapters is that they really arnt up to the job, you get about 3 threads of the bolt going into the plate and even with locktite I had one fall out on the motorway. Going to finally get my 4pots fitted on custom brackets soon.
i had audi/rocco 256mm setup on my cabby, that was more than good enough for my usage. if you arnt happy with 280s id wonder if there was someting up with it, check the bar across the bulkhead hasnt got too much free play, and upgrade the servo/master cylinder if you havent already. what you might want to consider next are vauxhaul calipers & carriers, they're pretty much bolt on fitment. need to use vaux pads and hoses, plus mk2 discs. can get em in 280mm and iirc pad surface is bigger, the only thing you need to do is either fit sleeves to the calipers, or use shouldered bolts (the holes in vaux carriers are bigger)
This is for racing so John is after the 280s I suspect. If the car has the original calipers, ie 239mm disc calipers, then the pot size is smaller than the 256 and G60 280mm calipers, at 54mm. I think the sub question is whether to bolt on 256 calipers, or whether to chase 280 calipers and what's the diff between the two (256 discs are 20mm wide, 280s are 22mm wide - are these interchangeable, barring pad wear, or will new 256 pads simply not go on 280mm discs?). Also recommended suppliers for caliper spacer brackets, preferably with more than three threads worth of bite for the fasteners!
256/280s are the same just thickness issue as you say, use part worn 256 pads and/or grind the sliders down. better to just fit the right 280mm calipers unless you need the thinner 256 for more wheel clearance
I never understood why those G60 280 adaptor brackets for a mk1 were made. If going to the bother of making up an adaptor bracket, why not use the 256mm carrier which is far more common and gives more room to manufacture the adaptor bracket too. I reckon there is the possibility of just plugging the existing holes in the 256 or 280 carriers, and then boring new holes to suit the mk1 mounting points.
Hi All, Many thanks for the responses !. The standard single piston calipers (Chris - spot on with the size ) need to go I believe, but as the car only has to be 950 KG with me on board 4 pots maybe unnecessary (as Mike suggests). Probably, as run by 2dubnick, the G60 2 piston caliper would be a good idea. I'm running 7x15 wheels and have to run the standard hubs unfortunately.....so it's the brackets again. I have to say that there's more than 3 threads worth of bolt in the spacers (phew ), which were originally from Autocavan. What are the thoughts on pad type based on track day use ?. I'm a fan of either EBC Yellow Stuff or Ferodo DS 3000 usually, buy would be very interested in others experiences. Kind regards, John.
My adaptors I found out where copies of the caddy shop ones and they clearly are not thought out well, might be 4 threads but the way they are designed fine thread bolts would of been better, anyway back on topic with pad choice iv got yellow stuffs on one car and ds2500 on another, I'd imagine ds3000 where always going to be the best for track only but I'm only going on what iv read. I'm tracking both my cars this weekend and I already suspect I'm going to get on better with the ds2500s and at almost twice the price I'm not surprised.
I asked the same question a year ago or so. And have decided to go with VR6/G60 280mm calipers (the same?) and mk4 calipers on the rear, with bias valve. And MC servo upgrade. DS3000 pads on the front, and experiment with pads on the back to get the right bite/feel. I used DS3000 with a totally standard 239mm brake set-up (AP fluid) and it lasted well on track. I could get the fronts and rears to just about lock (bias valve trials!) with hot 195/55/15 Dunlop Direzza's. Although still has the terrible mk1 pedal, and had to push it very hard. Need adapter brakets too. If you decide to go down the same route as me John, I could get 2 sets of adaptors made and split the costs?.... should be cheaper than just one .... and we could design them to be beefy. Will the 16v MC/servo upgrade reduce the pedal travel also?
Sorry only just spotted that, Im running seat ibiza 1.8t calipers which are Girling 54 calipers same as Corrado G60, not the Girling 60 twin pots found on Audis, the twin pots look too heavy and pad choice is poor with only yellow stuffs available as a track pad, though pad surface is massive in comparison, wilwood light weight 4pots do look the best for small light cars but some say its overkill.
AFAIK G60 calipers are single piston one sided caliper, as per early Mk3 GTI, and similar to the 256 16v caliper, in all the cases I've seen. Maybe you're using them a bit harder than me, John, but I'm only running M1144 pads on G60 single pot cailpers, standard Dot4 fluid, and some old grooved discs. I've never even been near to brake fade, on the 'Ring, or down the big hill at Cadwell, or hammering round the private test track at speeds that would be very illegal on UK public roads. I guess there are circuits out there that are harder on brakes, but I've not found them wanting as yet. Danster's point about 16v calipers is a fair one - they're a little bit lighter than the wider G60 caliper too, but you might have clearance issues with new pads and have to grind a mm or so off them, as the 280 discs are thicker than 256s. If you find you're running out of pad material during a race, you may need the thicker G60 pads just to last a longer race, but hopefully not. EDIT: I'm just re-reading your original post, and I'm now thinking you're using the original 239mm calipers, on spacer brackets. I have this setup on one of my Scirocco road cars, and it's nowhere near the stopping power of the G60/280 single pot conversion, although much better than the standard 239mm setup. I haven't used them hard enough to have a problem with fade, but the 'bite' when you hit the pedal is nowhere near what I've got with the other car (bigger master cylinder, servo, and the G60 calipers).
Just to complete the possibly ambiguous info, 239mm calipers have 48mm pots & 256mm & 280mm calipers have the 54mm pots.
Thanks again guys - good feedback all round. DS3000s look favourite as pads and I think I'll try the G60 calipers to avoid the potential pad clearance issues. Sam - I have some mounting brackets, but don't yet know if they'll be suitable for the G60 calipers. If you're getting some made count me in; particularly if they're very sturdy (but also very very light of course in line with the use on a race car !). Kind regards, John.
Thanks Mike They look quite good. Surely they would say the thickness? John, Ill let you know if I get any made
The G60 carriers are Mk2 spacing, which is wider than Mk1, so if you're thinking your current brackets will work, they won't.
