Blow-Off Valve installed !!

[Jin]

I have the APR R1 installed along with a CAI and the increase in noise far exceeded what I expected from a diverter valve. Obviously not as loud as a BOV but enough for me!

[RhysQ]

Is it just me or do BOV's seem to add a 'wank' factor. Or even turn such a nice Euro car like this into a boganesque Jap-like car?

1. i was experiencing some boost leak (mainly in third gear) and was told a good BOV can hold a lot more boost.

2. since having the BOV i've found that i don't get any leak and through third gear especially it holds boost all the way through....nice and smooth.

3. i personally like the sound, but would understand those who don't like the sound would consider it a 'wank' factor. it's a personal thing i guess.

4. majority of turbo race cars use BOV's and i wouldn't think they were going for the 'wank' factor.

sorry have no pics or vids up yet, the gf has the camera and keep forgetting to get it off her.

[Kai]

A plumback bov will always be better then atmo.

You are keeping more air in the system...

[GTIJNR]

dual port or not i think they still bleed out a fair bit of air during light on/off throttle cruisin... yeah i likes bov when i was a p plater lol.

[ryan_GTI]

i'm still on p's

[mitch_gti]

i'm still on p's

Copy that

[Spec83]

A plumback bov will always be better then atmo.

You are keeping more air in the system...

Depends if your car runs a MAP or MAF sensor

[Kai]

Depends if your car runs a MAP or MAF sensor

why

.....

[WHTPOLOGTI]

any video of it on youtube yet?

[Bubu]

why

.....

Its quite simple really. But first you have to understand what each one means.

MAP = Manifold Absolute Pressure

MAF = Mass Air Flow

A MAP sensor meaure the absolute pressure in the manifold to determine how much fuel to feed the motor. Therefore if the BOV vents to the atmosphere completely the MAP sensor will not detect the air and will not feed any fuel. On the other hand if the BOV is not an atmo then it will detect the air and it will give fuel as requiered.

The MAF sensor meaures the amount of airflow going into the engine, just after the air filter. Turbo cars that use a MAF sensor have the ECU programmed to feed extra fuel when the throttle is closed and the BOV has been opened to compensate for that air that is being re-fed into the intake from the BOV. Its important to note that the air from the BOV is fed into the intake after the MAF sensor. Therefore the ECU assumes that the air from the BOV is going back into the intake and has no way of knowing that the air has gone to the atmosphere. Because it assumes that the air has gone back into the intake it compensates by giving the engine more fuel so that it does not run lean. The car ends up running too rich for that brief moment and thats why it creates problems.
Factory turbo cars have the ECU programmed this way because they dont expect you to change the BOV to an atmo unit as this is against pollution laws in most if not all countries.

Obviously there is more to it than just that, but we wont get too technical to answear a simple question.

[Spec83]

Spot on explanation Bubu... it is also why you hear a number of wrx / sklines / silvias et al backfiring on gearchanges due to the engine running very rich and not completly burning all of the fuel...

Can also cause O2 sensor and cat converter issues in the long run

[Kai]

wooooooo

Thankyou for the info

[RhysQ]

pics and vid now up guys...see my first post

[VW GTI]

I hope it's louder for you than in that video. Especially if you wanted noise.

[Kai]

race?

I should have showed you the noise mine makes today.