twiztedjeckel
Member
- :
- '04 SVT Focus
so i hate to piss on your cheerio's but the valves may look similar but they sound nothing alike. matter of fact lots of oem bov's look alike but sound very different
BLoW 0fF valve
- Thread starter DJB00TS
- Start date
there is something called a street heat technical training guide that your local Mazdaspeed dealership has. you can't see it but the tech's have access to it and as i am reading it (cause i took it home) it clearly says "The Air Bypass Valve is adapted from the 3rd generation RX-7."
One of the guys at Motorsport Dynamics here in Sac. was going to hook me up with the BOV from his RX. I don't remember if it was a 2nd gen or 3rd...He said it had the same setup, but that it would give me the sound i was looking for with out me spending all that money...It couldn't be exactly the same BOV or there wouldn't be any point to me swapping them.
Adapted does not necessarily mean the same...If it was the exact same, they probably would have said "taken from the 3rd Gen. RX-7".
Adapted does not necessarily mean the same...If it was the exact same, they probably would have said "taken from the 3rd Gen. RX-7".
twiztedjeckel
Member
- :
- '04 SVT Focus
2K3 Mazdaspeed said:
good call. i'm not tech or anything but i'm guessing if it were the same bov it would make the same noise regaurdless of how much boost its running. it would be the same noise just quieter in our cars due to less boost. am i making any sense ehre with this?
twiztedjeckel
Member
- :
- '04 SVT Focus
2K3 Mazdaspeed said:aside from the punctuation and spelling, you are...
i'll make a note of that and go back and punch my english teachers right in the mouth....all of them
prefectly good is stretching it a little...first is the size of a silver dollar and its plastic...and you think its going to hold boost.......????
I agree..
Its not set up to hold boost. I bet it would not hold 11psi.
For a first mod you need to look elsewhere.......My first mod would be a boost guage.
the stock BOV sucks. sorry. I come from a world of DSM's, Supras, and RX7's. Ive seen good ones, and ive seen really sucky ones. For instance, Saab and Porsche have nice ones. MKIII supra has a sucky one. 1G Eclipse/Talon/Laser have REALLY good ones, 2G Eclipse/Talon have really sucky ones.
Just cuz its original doesnt mean its good. Just cuz the outside of the BOV is the size of a silver dollard doesnt mean the actualy orifice is that size. the diaprahgm is silver dollar size. Ill be that the actual orifice that air passes thru is only about the size of a nickle...thats tiny. Not very good when considring the more air it flows, the better the turbo stays spooled. and Yes, im sure it will leak air underboost, Not just partial throttle, but any high boost. so anytime the turbo is fully spooled, its probably leaking. 2G Eclipses (FASt and furious style) had all-plastic BOV's and leaked at anything over 12 psi...and they have the same Garret T25 turbo, except it was standard wick-type bearings.
Your initial Mods should go like this:
Autometer Pro-Comp Boost guage -20/0/20psi (never trust a factory guage, you poor guys dont even have THAT
)
K&N intake w/ some kind of heat sheild
Shorter intercooler pipes (the stock setup is a clusterF*ck)
BOV w/ reciruclation kit (HKS or Trust)
Big FMIC
2.5" downpipe
3" cat back exhaust
Leave the boost as it is for a while. Im not sure how the fuel system can handle added boost, plus i know the motor cant. The motor is basically the same as the ES protege w/ a turbo kit on it. It still runs 9.1:1 compression ratio, which is SKY HIGH for a turbo applicaction. And im 99% positive that they are cast aluminum pistons not meant for a turbo application. which means they wont hold up to high boost levels, excessive detonation, or high EGT's.
However, you can make it last and make some good power w/ the motor IF, and only IF, the engine is tuned very well. Not tuning it is what will kill it.
Btw, a dump valve and bov do the same job.
Just cuz its original doesnt mean its good. Just cuz the outside of the BOV is the size of a silver dollard doesnt mean the actualy orifice is that size. the diaprahgm is silver dollar size. Ill be that the actual orifice that air passes thru is only about the size of a nickle...thats tiny. Not very good when considring the more air it flows, the better the turbo stays spooled. and Yes, im sure it will leak air underboost, Not just partial throttle, but any high boost. so anytime the turbo is fully spooled, its probably leaking. 2G Eclipses (FASt and furious style) had all-plastic BOV's and leaked at anything over 12 psi...and they have the same Garret T25 turbo, except it was standard wick-type bearings.
Your initial Mods should go like this:
Autometer Pro-Comp Boost guage -20/0/20psi (never trust a factory guage, you poor guys dont even have THAT
)K&N intake w/ some kind of heat sheild
Shorter intercooler pipes (the stock setup is a clusterF*ck)
BOV w/ reciruclation kit (HKS or Trust)
Big FMIC
2.5" downpipe
3" cat back exhaust
Leave the boost as it is for a while. Im not sure how the fuel system can handle added boost, plus i know the motor cant. The motor is basically the same as the ES protege w/ a turbo kit on it. It still runs 9.1:1 compression ratio, which is SKY HIGH for a turbo applicaction. And im 99% positive that they are cast aluminum pistons not meant for a turbo application. which means they wont hold up to high boost levels, excessive detonation, or high EGT's.
However, you can make it last and make some good power w/ the motor IF, and only IF, the engine is tuned very well. Not tuning it is what will kill it.
Btw, a dump valve and bov do the same job.
