After cooking my fluid at Donington Sunday, It's maybe time I used something a bit better than the 'free' DOT 4 I get from work. Been looking around on the 'net and have found some good info regarding wet and dry boiling points and the like. Castrol SRF is the dog's danglies fluid but needs to be changed regularly due to it being more hydroscopic (absorbs moisture) than other fluids. Ate's super blue is highly recommended - "ATE Super Blue (DOT 4) has a dry boiling point of 536F and a wet boiling point of 396F. ATE Super Blue is identical in specification to the ATE TYP 200 brake fluid. ATE Super Blue is compatible and will mix will any DOT3, DOT4, or DOT 5.1 Fluid. This top-of-the-line product lies 20 C over the DOT 5.1 standard and surpasses this standard in nearly all the other requirements as well. This means that cars can go without a brake fluid change for up to 3 years while products with a lower wet boiling point have to be replaced considerably more often (e.g. DOT 3 products should be replaced annually). The overall high dry and wet boiling points make this fluid an excellent choice for street driven vehicles where brake fluid is flushed less frequently than in racing cars. Also, the blue tint of the fluid makes bleeding brakes easy!You can easily tell when you have flushed out the older fluid." Sounds good to me Edited by: G_V_K
<deep breath> a lot of money for brake fluid SRF is 38:33 + vat from Demon Tweeks (1 litre) Ate is about 20 a litre I'm going to bleed it out with DOT4 this week to keep me going over the winter, then get some proper stuff before next year's track days.
was looking at this when ordering copper nickel piping on automec, heard anything about it? litre is 20 quid
You really don't want to be using silicone fluid on the road unless you are going to change it extremely regulalrly. It will not mix with water so when water does ingest into the system it will sit there and corrode your pipes and when the water is in you will get a very funny pedal feel. There are some DOT4s out there that seem to perform better than allegedly better DOT5.1s. Motul RBF is one I believe.
I use the Automec stuff and so does my m8 in his mk1 g60, i found it great for track days, pedal height never changes even when the brakes pads are up in smoke. BUT !, other people will say they don`t like it because it can make the pedal spongy. The last time i had it MOT`ed it had a note saying pedal spongy ( not a failure item) I have no problems with the pedal feel ( i drove a mk1 far too long to worry about this ) i like the fact that it never needs changing either.Brake setup is , 280mm on a late 16v with goodridge hoses Ate's super blue is sounds very good but could get expensive i suppose http://www.automec.co.uk/frame_set.html Edited by: dUff
where can you get the ATE super blue stuff from?? looked in tweeks new catalogue and they don't stock it.
Water can get in at any join, seal etc through porous holes in rubber tubes. That's one of the reasons why you have to change glycol fluids after 2 years. Yes, they are hygroscopic but the water still gets in.
Makes no difference, you will stil run the same piping etc so water can still ingress in exactly the same way. When it is in, it will not mix with silicone (which it will with glycol) which can result ina spongy pedal as the 2 fluids now present remain seperate. The point I was making about gycl is that it mixes with water and thus reduces the effective boiling point of the new-mixed fluid. So you replace it. If you have silicone great, but when you introduce water it will boil at a much lower temperature and give you that spongy pedal feel through different BPs and possibly also from the 2 fluids not mixing and possessing different properties. For the road you are best off sticking with glycol. Use DOT5.1 and you will still possibly have to change it more often than every 2 years because the water will reduce it's high BP. Edited by: edc1
well brakes are to be brembo 4 pots with 305mm discs, copper nickel piping, brass unions, passat servo and 16v master clyinder and braided hoses, so don't want to use cheap fluid just somehting to haul it all down.
DOT5.1 or Super DOT4 (look at the specs some DOT4s are better than DOT5.1s I'm told - the DOT ratings are only minimum standards) should suffice.
GVK found a great site last night... DOT 4 is a BETTER performance fluid than 5.1 -- 5.1 was more show car oriantated as it doesn't pose a danger to paint etc... etc... The problem with Dot 5.1 is that water can get in, it wont mix and it will boil vey early on comapared to the brake fluid.. this can cause a hydro lock type affect and lock your brake system out ompletley. Nice!
i hate my pedal feel..can't get it right. it's relatively long, and spongy (there is no air in the system tho!!) i like a pedal to have a really short travel and be very very firm. am currently using DOT5.1 (not sure of brand but just normal motor factor stuff). what the best reasonably priced stuff? would vw owns be best? (dunno if they do anything other than DOT4 tho)
