ducting parts

[Dark]

got these parts from demon tweaks

i think i have got the wrong size intake duct though, i need a slightly smaller one for where i want to take my custom induction from. if anyone want to buy it for there upgraded ducting to airbox or aftermarket filter then let me know. it fits perfect behind the lower bumper grill as pictured,

i checked this so it could be useful to someone else, it hasn't been "used". my black catch tank is about to arrive, and to set everything up like i want to i have decided to get a BMC CDA, as this will allow me to have the space and flexibility for my custom ducting setup. pictured is where i will be taking the inlet air from, enlarged hole behind upper grill.

[foxy]

Looking good, but are you not going to pipe the breather back into the air feed to keep the vacuum?

[Dark]

i'm not sure yet. will either do that by getting a self sealing tap off part for silcon hose ( from demon) then plug in the exit hose from tank. or i might duct the outlet from tank in an unrestricted way down to bottom of engine bay and facing rearwards, so in a negative pressure area, not as good as the engine vacuum, but certainly better than attaching one of those "breather filters" to the tank outlet. i think this is how track/rally cars are done, they disconnect the crankcase so the non oxygenated air doesnt go into the TB. but racing regulations say you cant have free oil vapour in the bay, so it has to be caught in the tank 1st. possible fire hazard? i dont know.

Edited April 11, 2008 by Dark

[TomLS]

The thing about removing the breather is that even if you can route it somewhere that the fumes won't bother you, the loss of strong negative pressure in the crank case can cause a previously dry engine to start leaking oil.

As far as performance goes - unless you have some bad blow-by I promise you'll never notice the difference. The expulsion of hot oil vapour is a few cc's a second, in the same time the engine draws 1000's of cc's of air.

[SC02 FFF]

how much this set cost you? will it snapp all together to fit a bmc? ill buy it!!

[Dark]

The thing about removing the breather is that even if you can route it somewhere that the fumes won't bother you, the loss of strong negative pressure in the crank case can cause a previously dry engine to start leaking oil.

As far as performance goes - unless you have some bad blow-by I promise you'll never notice the difference. The expulsion of hot oil vapour is a few cc's a second, in the same time the engine draws 1000's of cc's of air.

everything counts though . i don't think its just oil vapour that comes out of the crankcase breather, feels mostly like air when the hand is over it. i'm just guessing but the engine is supplying the same suction to the diameter of the breather hose as the cold air inlet, the mm difference between the 2 bores would give a ratio of what dead air your getting to good air? about 20%. it probably isnt that simple, but in cases when a lot of useless gas vents out thats the maximum potential draw. and on that crucial overtake manoeuvre it could do without being there.

Edited April 12, 2008 by Dark

[Dark]

how much this set cost you? will it snapp all together to fit a bmc? ill buy it!!

i'd sell the black intake duct for £16 including postage. cost me £21.10 inc postage.

as pictured it can use 2.5" or 3" ducting to go to wherever from the lower bumper grill, use flexi hose ducting available in 1m lengths to get from intake duct to filter.

if you mean a whole kit in the different way i'm doing it will let you know how much that is once i have finished it.

[CasperGTI]

Most of the fumes you get out of the breather is hot air with a hint of oil in it. Or atleast thats what i think as my catch tank normally has more water from condensation than oil in it.

Removing the vacum itsnt too bigger deal, infact i dont think its any deal at all. It prevents the TB from getting clogged up and supplies the engine with a good cold supply of clean air.

I always thought the breather was there to equal the pressure between the top and bottom of the engine... no imbalance in pressure therefore no unequal pressures on seals, Unelss you have a labrinth or carbon seal in the engine? (these require pressure on side to make a better seal) can someone tell me different?

The only point i could see against this would be the fact that the breather air is usually quite humid, thus mixing it with the fresh air on the way to the TB would increase the density of the air entering the engine, making it more combustable. These engines arent mapped precisely enough for that to make an effect though IMO.

Dark has done the same thing as me, Ive routed a pipe from the catch tank to the bottom of the engine bay coming out behind the skid tray, facing rearwards hoping the negative pressure caused by driving would create the vacum. I dont actually think the vacum will be much higher than this if it was in the air feed anyway. Think of the air flow at full throttle to the TB and the airflow at speed under the car? gotta be pretty close hasnt it?

Dark, i like the ducting.... would it work to fit a bmc following the route of the original intake pipe past the charcoal cannister to the bottom grill?

John

Edited April 13, 2008 by Casper1496

[Dark]

yes could use similar ducting, cant use the 45deg section though, thats half the reason i'm not going that way now. need another 90 degree instead to go in that direction. then flexi ducting to connect that down to intake duct at lower grill.

edit: actually the 45 degree might go from the bmc filter, and then over to the 90deg towards the air inlet, but the 75mm tubing i have will not fit down towards the lower grill. need 63mm/2.5" tubing. which you can also get, and would be a bit cheaper also, but will need more sections to get there unless as said you just use flexi 63mm ducting from the grill intake upto the engine bay where the alloy tubing starts. depends what you want really.

Edited April 13, 2008 by Dark