freaky shit, I was going to ask a similar question just now, the threads ancient, thats just fait that this was revived from the dead :lol: LOL

this was over a year ago !! grr grave diggeeeeeer

If you pass too much vapour back into the inlet it can cause excessive carbon build up and pre-ignition and detonation. It also lowers the output of your engine it kinda defeats the object of putting say optimax in if its pumping gasses into the inlet which has the opposite effect that the higher RON rated fuel has. It wont be a significant difference but on say a high boost aplication it can dramatically effect the amout of boost you can run!!!

in addition to the lubricating, its there as part of the crank case ventilation system, in the olden days this used to vent to atmosphere underneath the car, it vents blow-by gasses and toxic oil vapour that collects in the crankcase.

These days all vehical emmisions must be vented through the exhaust, so they are drawn from the crankcase via the rocker cover through this pipe then re-burned and shoved through the exhaust pipe.

Hope that helps a bit!

Dave

ps if you do a google search for positive crank case ventilation there are loads of topics on it

im gonna get a catch tank, im liking doing engine stuff now :)

cool

http://www.migweb.co.uk/forums/showthread.php?t=138550

get a catch tank from think automotive i paid 100 quid for a chrome 1 then get some pipe then bobs ur uncle :)

oh and dont block it up as your car will piss out blue smoke

i asked this exact question on mig yesturday, basically you need to keep it there as it lubricates the turbo and stops the veins rusting up. however a oil catch tank is the best option, but the chanes are there isnt much oil that goes down it anyway.

i think the vapour is from the sump its what gets past the piston rings?????, i had a 7mm gouge in my no1 cylinder wall due to gugeon pin coming detached and man was there some vapour, my car became a kettle lol

i've heard people say that the vapour acts a lubricant and rust prevention on the fins of the turbo? Or is this just crap?

[Edited on 14-07-2004 by MattyB]

you could but id advise a filter too

Oh rite.....so i could run some 1" pipe down and away, and just leave the end open?

i dont see where the 'vapour' comes from? just from round the cams and stuff?

Matt

its for environmental purposes, oil vapour is a little toxic, my breather runs down behind the front arch liner and exits towards the floor, ya dont want toxic vapour in ya engine bay, it smells and gets sucked into ya air vents and blown into the cabin,

dont block it
ak did it with a bit of pipe a small sprite bottle and a breather filter

cool but i'd rather just not spend any money on it at all! lol.

Could i not just block it.

you can make a oil catch tank and put a breather filter just after it, itll be ok

I am considering a rethink of my induction set up which will involve removal of most of the standard OE induction piping, coz its too long and very restrictive.

At one point, a breather pipe (coming from the the rocker cover), joins the induction pipe (i've seen this on many cars), obviously carrying oil vapour.

However, why is it there? What is its use? What problems will i come accross if i remove the pipe, and replace with a little piper X breather filter thing.

thanks

Matt

PS: note, mine is a turbo, so are they any extra problems this could cause?

[Edited on 14-07-2004 by MattyB]