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Guest hybrid2nr

The ricers over here still don't understand why atmospherically-vented BOV's on engines with MAF sensors make them give off a puff of black smoke when they lift to shift. They'd rather have that goofy noise than have their engines run correctly. Shows you where their priorities are at.

You would have to assume that people are aware that if the BOV is changed so it vents to atmo there will be problems. This is because when all that air the MAF has just measured which it thinks is being vented into the intake (after the MAF) but isnt will mean there is less air in the system. As a result it dumps enough fuel into the engine for the vented air and the air coming through the MAF ie there is less air than the computer thinks and it gets too much fuel (floods the engine stalling it).

In short dont go the aftermarket BOV unless you can plumb it back. I am making an adaptor for my SSQV to plumb back so i dont look like a twat and have my car stall at the lights.

  • 2 weeks later...

Let me know how it works out, cause I'm thinking of getting one, and wanted to know what they are like from someone who actually has one.

I found out that my stock one is leaking.... I took it off, and blew air into it from the inlet and it just leaked through the other side.

Wierd.

  • 1 year later...

its not MAF cars that run rich/overfuel on shift coz of BOV's, its AFM cars isnt it? MAF = mass air flow like what aftermarket ECU's use which *stop* overfuelling from BOVs.

whereas stock cars have plain hotwire Air Flow Meter which overfuels with the atmo bov.

but yeh the point was right that they cause overfuelling.

its luck of the draw tho how bad or watever depending on many factors.

my DR30 skyline has an old Jap bov of some sort, with it D/C there is noticable lag on shift at 1bar boost pressure. with it reconnected there is noticeabley less lag, even tho its slight and mostly see it on slower shifts.

getting a hybrid 600x300x75 cooler installed over the next 2 days along with a Sard R2D2 BOV, so we'll see how that bad boy goes !

romeo - yeh i think u can get electronic BOVs for non turbo cars but ... please dont. lol its so lame. !

roy - ah right yeah i got confused also. pple interchange the terms too much these days. so AFM = Air Flow Meter which is a Mass Air Flow sensor system, whereas MAP is Mass Air Pressure and is just a MAP sensor and has no other name?

how exactly does the MAP not be interupted by a BOV then? wouldnt the pressure drop wen the bov releases and confuse that too? im totaly unsure of the principle behind the MAP sensor so this may be a stupid suggestion but im sure some1 will clear it up for me!

cheers dudes!

'] wouldnt the pressure drop wen the bov releases and confuse that too?

In a brush stroke explanation , when it senses the drop in manifold pressure it guesses that there is a drop in cfm so drops the duty cycle on injectors, (less fuel injected) so doesnt experience the same dramas as AFM equipped cars.

Is the HKS SSQV plumpback or vent to atmosphere?

T.

Vents to atmoshpere only.

I've got one. When I had the standard intercooler and was running standard boost, I hated the sound of it. Sounded like some puncy little train whistle, or a gay guy on Oxford street checking out my ass...

after increasing the boost, it sounds a lot more aggressive and masculine... makes me feel like all 80kg of masculine rice boy. :cheers:

Nah - they're pretty good but as I say, sounds fairly camp at low boost..

Giles

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