So chaps, what's best for a track and fast road ST205 on standard calipers running yellow pads?

Ran RBF600 in the Mini with good results but dunno if that's suitable for the ST205's older spec seals etc.

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02 Mini Cooper Race Car
94 ST205 Import
92 ST185 Carlos Sainz
www.mcnab-racing.co.uk

Hi,

DOT4 is perfect

greetz

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KEEP COOL UNDER PRESSURE

street legal?.....perhaps in tschibuti

or 5.1

avoid dot 5 as it's not compatible.

I'm sure oilman did a write up on brake fluids somewhere.

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If at first you don't suck seed, try drier grain.

Hi,

DOT5 is a silicone bases brake fluid just for race use (do not allow the water to bond with itself)

DOT5.1 is like the other specifications a glycol bases fluid for road use (water will bond with it), the issue is they higher the specification they more aggressiv is the fluid which can occur damages seals, rust and non working brake pistons
(a friend of mine and mechanic confirm this to me)

the system of our cars is build for DOT4
i will go for millers oils racing brake fluid 300 plus (DOT4) if it helps


greetz

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KEEP COOL UNDER PRESSURE

street legal?.....perhaps in tschibuti

Hannibal has been running DOT5 for years now with no ill effects

TBH I just run generic 5.1 in the black car and I've never experienced any issues on track with it even when rurnning hard enough to blue the disks. Maybe over the course of a full distance race differences would become apparent but for the real world I personally find no difference between race spec dot5 and halfords spec dot5.1

My understanding is that dot 5 was developed for high performance road use with the silicone base to avoid the rust problems. The downside is that it is more compressable and leads to a spongy pedal, hence why it has never taken off.

Never tried the stuff, just going by what I've been told.

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If at first you don't suck seed, try drier grain.

Hard to comment on that one

Both mine are equipped with ABS and I find the pedal (In common with every gt4 i've driven) about as firm as Bella Emberg's butt. There's no lack of power but a distinct lack of genuine pedal feel
If anything Hannibal is slightly better on dot5. Both are rock solid unservod though

I drove one with a very solid brake once, but nowhere seems to make brake master cylinder braces anymore

If you watch the servo and brake cylinder when getting someone to mash the pedal its ridiculous how much they flex.

Think I'll go with some Halfrauds special 5.1 for ease and cheapness (tradecard ftw!)

I would throw in some RBF I still have sitting around but I remember hearing there's a compatibility issue of some sort with this and other fluids so you sometimes have to flush the system fully which is more hassle than I'm after for a marginal gain in performance. Also my RBF600 sucked in water and crap at an annoyingly high rate.

Hi,



great and underline the quatity of toyota parts

the issue is when water don't bond with the fluid that there is a chance of water vaporisation when hot which means braking is not 100% safe

(the fluid becomes hot while braking -> you put off the food from the brake pedal -> pressure lowers -> water vaporises [boiling point ~100°C at atmospheric pressure] -> you pull the pedal again -> now the damp becomes compressed -> no brake power)

race cars do not have the problem as they become the fluid changed every race, i would not advise to use DOT5 for road cars with long changing intervals even it works

greetz

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KEEP COOL UNDER PRESSURE

street legal?.....perhaps in tschibuti

Similarly, one of the issues with dot5 is it's not hydroscopic. In fact I believe it's hydrophobic. This means any water that does get in (condensation on the mcyl cap for eg) pools in the lowest point or wherever it gets stuck. typically wheel cylinders and abs pumps

I use Castrol SuperResponse DOT 4 in my car, seems fine, been using it for about 6 years now.

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GT4DC Events Co-ordinator
1996 ST205 UK

factory spec is dot 3, however i swapped mine out for a generic dot 4...great feel


check the st205 specs, youll see that dot 3 is called for (but as stated, put in the dot 4 for intense duty)

Thats true Whitie - although I am not sure if you can even buy DOT3 anymore?! I don't recall seeing it for a long time.

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GT4DC Events Co-ordinator
1996 ST205 UK

I know this post hasn't been touched for a while but I was checking my brake fluid yestaday and it needs topping up and as stated above, it takes dot 3. Is it ok just to top up with some halfords universal brake and clutch fluid dot 4..... ?

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1998 ford st24, 186hp 2.5 v6- sold
1997 bmw e36 318ti, mint hellrot red- sold
1992 celica gt4 st185- td04 340hp/330lbs
1998 mercedes E280- sold
1998 pug 1.9 td- mile muncher!
1993 rx7 542hp savage monster!!
2007 BMW 335i- in the shop gettin built!!

yes.

_________________
If at first you don't suck seed, try drier grain.