28 whp swapping bpv for bov speed3

[shadyspeed3]

watch and see. i gotta believe these numbers are legit. we will see when i get mine!

http://videos.streetfire.net/video/Synchronic-BOV-Mazdaspeed-3_156202.htm

 

[Picklz]

Until I see some numbers from community members (before and after) from the same dyno and similar environmental conditions I'm extremely skeptical, a few hp I could maybe believe but 28whp .... I duno.

 

[Big Nate]

Well the BPV is the only engine mod I am going to do. So it will be nice to see what it can do to my car too.

 

[Workdawg]

Someone else posted this as well. From my understanding, the only way a BOV would make power is if the stocker is leaking, and if that's the case, wouldn't any replacement provide those gains?

 

[dmention7]

It's already been discussed quite a bit here: http://www.mnmazda.com/forum/showthread.php?t=1357

The consensus is one of three conclusions:

a) The numbers are bunk.
b) The person's stock BPV was leaking like a mofo, and this will be a hit-or-miss solution depending on the consistency of the stock BPV
c) All stock BPVs leak, in which case any upgraded valve is going to give you similar numbers

The main thing that calls the results into question is that they conclude their BOV made power by allowing the car to hold more boost and hold it further up the tach. This is sketchy for two reasons: they didn't show an "after" plot of boost pressure to prove an increase (they showed a before but not an after = wtf??), and also the dropoff in boost at high rpms is directly caused by the ECU, and possibly only exacerbated by a junky stock BPV.

Finally, they were screwing around with "bad gas" and octane boosters during the first two runs, so even the baseline numbers are sketchy.

 

[mazdamn02]

Mazda gets their stock BPV from a "claw" arcade game in a Japanese Perkins.

 

[mndsm]

Wouldn't that be a "craw arcade game in a Japanese Pelkins?"

 

[dmention7]

noob.... they don't transpose r's and l's.... they just pronounce their l's as r's

 

[spek1098]

Yea, some where I read where they were explaining why VTA actually causes loss of power due to rich spikes caused by the unexpected, to the ECU, loss of oxygen.

He's some thinking from Josh at Cobb on VTA as it relates to tuning with the AP
http://www.mazda3forums.com/index.php?topic=100754.msg2090562#msg2090562
http://www.mazda3forums.com/index.php?topic=70867.msg1977073#msg1977073

 

[dmention7]

Well, running VTA without some kind of tuning is generally going to cause the car to run funny. Reason being, these cars rely on the MAF sensor for fuel metering. If you are venting to atmosphere (BOV), you are taking air that has already been metered by the MAF sensor and venting it from the intake system. So suddenly for a short time you have less air going into the engine than it thinks, thus you get a brief rich condition.

For the MSP, a common trick is to relocate the MAF sensor to the IC coldpipe, downstream from the BOV. That way, when you are VTA the air being released is being released before the MAF meters it, thus no momentary rich conditions.