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Brake MC - Exhaust too close?
speedyxjs - 25/9/09 at 07:39 AM

My exhaust is going to run about 2" below the brake master cylinder. The exhaust will be wrapped in exhaust wrap. Is this going to cause a problem with the temprature of the brake fluid? If so, would a heat sheild help?

Edit - to change the 1" to 2"

[Edited on 25-9-09 by speedyxjs]


madrallysport - 25/9/09 at 07:40 AM

I would fit a heat sheild, 2" still is pretty close.

(its still close at that)

[Edited on 25/9/09 by madrallysport]

[Edited on 25/9/09 by madrallysport]


speedyxjs - 25/9/09 at 07:43 AM

Sorry, meant to say 2". Have changed it now


Bluemoon - 25/9/09 at 09:09 AM

Not ideal, but not sure how close is o.k. Could you change to pendulum or floor mounted pedals to get the most clearance??

Dan


02GF74 - 25/9/09 at 09:32 AM

TBH I don't like the sound of that.... and I don't know how hot the master will get even if you use wrap and heat insluation.

thing is, the cap is vented so moisture, albeit, small amount will enter and mist with the fluid in the master, the same fluid that is pushed by the brake.

if the mater gets too hot, more than 100 C, the water will bubble = poor brakes plus I don't know how happy the seals will be at that temp, I suspect not very

Can you not route the exhaust?

I would suggerst boxing in the master using heat insulation stuff then running the enigne with a temp probe in the box and see.

Maybe construct some sort of vent with a small fan for cooling?

Anything over 50 C would be a worry to me.

note this is all according to my gut feel so I may be talking out of my arse - but I am not aware of production cars having hte brake system so close to the exhaust. You may need to google for how close this has been done on race cars.

see here; probs be ok if enough wrap is used

[Edited on 25/9/09 by 02GF74]


ashg - 25/9/09 at 10:01 AM

ask gkd about manifolds running near to brake master cylinders. the manifold on their bmw powered legend is about an inch away from the master cyl. i do recall them having to fit remote resevoirs so that it didnt melt.

i would think it will be more resiliant that you expect but it cant be a good thing especially on a track day etc.

the best thing you can do is fit remote resevoirs, wrap the exhaust and fit a little silver heat shild infront of the master cyl.


Bluemoon - 25/9/09 at 11:00 AM

Just remember brake fluid can catch fire..

linky

Dan


David Jenkins - 25/9/09 at 11:39 AM

I was going to say the same thing - apparently brake fluid spilling onto exhaust manifolds is a significant fire risk in accidents.

I'd be tempted to put a metal shroud around the M/C.

[Edited on 25/9/09 by David Jenkins]


speedyxjs - 25/9/09 at 01:06 PM

quote:
Originally posted by 02GF74
Can you not route the exhaust?



No. There is barley room the the exhaust on there atm


speedyxjs - 25/9/09 at 01:07 PM

quote:
Originally posted by Bluemoon
Just remember brake fluid can catch fire..

linky

Dan


That link says:

'DOT3, DOT4, and DOT5 all burn, and all about the same.'

What about DOT 5.1? Isnt it made of different stuff?


britishtrident - 25/9/09 at 01:17 PM

It is Dot 5 that is made of different stuff DOT 5.1 is just an improved DOT 4


David Jenkins - 25/9/09 at 02:00 PM

Can't remember the DOT reference, but 5 or 5.1 is silicone fluid - avoid at all costs! It may be non-flammable, but it's a total PITA to use and gives a soft pedal feel.

It's really only of use for collectors' cars that may sit around for ages.


Staple balls - 25/9/09 at 02:06 PM

dot 5 is evil (silicone based)

5.1 good