View Full Version : Could this be a step backwards or free performance?

Giga Shadow
04-24-2004, 07:54 AM
I think I spelt performance wrong... Sorry, it's late. :shock:

What I always used to do to all my cars was to cap off the niple on the T/B that got the breather hose and left the breather to vent into the air.

I thought that it kept the hot air from getting breathed, improving performence.

Then I was thinking, maybe the breather needs to be under vacuum when driving...

Does it run alittle bit richer with the hose detached.....?

I have it attached right now just because the smoke was going into the vent, but noticed some smoothness at start up and idle...
Then again, It was most likly in my head.

What are you're opinions about this.
I still think it's better to vent it to the air. :idea:

04-24-2004, 12:27 PM
more performance yes. ive been doing it for a few years now. now im turbo so i have to. but it also increases the pressure in ur block and head. which suposedly wears stuff out faster. i hope someone else can chime in

stuff=i dunno

04-24-2004, 01:05 PM
the purpose of the turb from the valve cover to the tb is to pull oil vapor from the vavle cover so the vavles dont sludge up over time. but, it would take quite a while.

slight performance increase yes, but i dont know how much if any that you will notice. the only bennifit will be a slightly colder intake charge. and if anything the car will run a fraction leaner because the oil vapor from the head has some flamable probertys to it. its not as combustable as gasoline, but it also helps to lubricate the combustion chamber.

like swartz says, if the vavle cover is blocked and cannot breath, it will pressurize the block and it can kill pistion rings (promotes ring blow by) vavle seals, or a whole slew of other minor things (pop the dipstick out, force oil out the oil fill cap, or the vavle cover gasket.

so, all in all i dont know if its realy worth it. the hp gains are minimal if any. and its there for a reason. know what i mean? but i dont think it would harm anything if you put a filter on it. maybe after a few hundred thousand mile you might gum up the valve train.
if you like the breather, but dont like the smoke, plumb the breather line to a catch can. but make shure you dont have any low spots where the fluid can condense and puddle. in the winter the condensation can freze and block the line and prevent breathing. i know about that one first hand :smt013

04-24-2004, 06:10 PM
If the block is pressurized from messing with your breather hose, I can see some power losses from the pistons moving against higher air pressure below them. I would expect your engine to prefer to operate in a vaccuum. Speculation of course.

Giga Shadow
04-24-2004, 09:08 PM
Another Idea that I had, was to drill a much bigger breather if your worried about that little hole makeing pressure..

Speaking of the Dip stick popping out.
That's happend to me, but only in the bmw, lol.
I never thought about the vapors actually helping lubracat the cylinders.. Makes sense.