I have just seen a picture of a K&N fitted to an ST. I see the crankcase breather pipe is sent to the K&N filter. Is it just me or does this seem an inneficiency in the system, as the air coming out the crankcase is hot, therefore putting this into the K&N would add to heat soak. However i suspect that not a great deal of air exits the crankcase, can anyone confirm????

Crakcase breather filter ftw

only time you will get heat soak m8 is when stationary with the engine running.
once you start moving the engine bay fills with cooler air and the heat soak will be gone.
so i would'nt worry about the oil breather m8.

Heat soak is only really present with forced induction engines anyways normally asperated cars rarely get hot enough for Heat soak to effect the car.

but you are right, there is small filters i've seen for crankcase air breather but honestly speaking wont make a difference to performance.

well Mountune see fit to route the crankcase re-circ straight back into the inlet (emmissions regs) so it can't really be much of an issue, my throttle body is always spotless shiny too. So your part right, perhaps few vapours do make it through but to little effect. It can only be better though if you can keep any air cooler that is going into the inlet whether outside or recirc air.

Focus ST's/ RS's suffer from heat soak badly when run on dynos.

But remember when you're driving along if you have cold air feeds going to the k&N its going to stay fairly cold so i wouldnt worry!

had mine running 15 minutes when I waited at the airport. Didn't notice any signs of heating so don't think it's an big issue

You won't get heat soak in this weather that's for sure brrrrrr
Get a MT CAIS maybe?

haha I always thought people meant there could be overheating problems when you stood still or was in heavy traffic. Guess I learnt something new today then:)