anyone using aftermarket BOV
01-18-2004, 04:59 PM
#2
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It's not that they are not good for the car, they are not good for performance. Allowing the turbo to de-spool somewhate between shifts causes extremely rich conditions as well as just plain making the turbo slower to get back on boost. But, if you like the way they sound more than you like getting back on boost half a second faster, go for it. Won't really hurt anything.
01-18-2004, 08:32 PM
#3
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I didn't know they actually decrease your performance. I just thought they didn't help. In fact, i think i read some post that said that bov's can actually help quicken spool times. But then again, can't believe everything you read.
01-18-2004, 09:25 PM
#4
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If your worried about loosing some performance go with somthing like a GFB 50/50 BOV. it shoots half the air out and half back into the intake. the stock BOV shoots 100% of the air back into the intake.
01-19-2004, 11:13 AM
#5
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i had a 100% atmospheric (no recirculation) valve on my WRX for about a day. It sounded awesome, but thats about where the benefits ended. The car idled kinda funny and after a few high load passes i got a CEL form my Air Flow Sensor. The wrx really is meant to have the air circulated back into the intake so DLUX WRX gave some good input, get one that is 50/50 APS makes a sweet adjustable one as do a lot of other companies.
01-20-2004, 03:21 PM
#9
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Originally posted by WindingRoad
i have a hks and i dont experience any power loss but no power gains. its just for the sound. my idle is still solid.
i have a hks and i dont experience any power loss but no power gains. its just for the sound. my idle is still solid.
01-20-2004, 04:20 PM
#10
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ok yalls, goto ask people that kno wats up with how turbo works.
first of all the hks bov WILL decrease performance if u are running a stock setup with the aftermarket BOV, in this case its only for sound.
the BOV is neccessary ONLY if you boosting high. such as turnin up the boost or if u have a bigger turbo. in this case, the BOV increases performance.
its all about a balanced setup. lota suckas jus slap things on thinking itll upgrade performance. its all about application.
first of all the hks bov WILL decrease performance if u are running a stock setup with the aftermarket BOV, in this case its only for sound.
the BOV is neccessary ONLY if you boosting high. such as turnin up the boost or if u have a bigger turbo. in this case, the BOV increases performance.
its all about a balanced setup. lota suckas jus slap things on thinking itll upgrade performance. its all about application.
01-21-2004, 09:27 AM
#11
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I have a GFB 50/50 BOV on my car. I ran it 50% recirc / 50% atmo. for a few months then switched to 100% atmosphere to just see what happened. I've haven't had any problems with 100% atmos. and have had it set up that way for about a month or so. Idle is still normal, no problems when shifting, and the sound is sweet. BOV's aren't really necessary on our cars, unless you're running really high boost but they sound cool. I'm stage 2+ so my car has a bit higher boost but a BOV still isn't necessary. If you want the sound and have some money go for it, if not it's not really worth it. I got mine used for cheap, and I like it.
01-21-2004, 06:28 PM
#12
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I have the forge 100% VTA , no problems for almost 2 years.
Everything i have done to my car is worthless in some elses eyes , but it makes me Happy...words of wisdom .
Everything i have done to my car is worthless in some elses eyes , but it makes me Happy...words of wisdom .
01-21-2004, 08:19 PM
#13
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an aftermarket BOV may or may not affect performance and any affect is small. the main reason for getting one is the sound.
first off the main reason the stock valve vents back to the intake is emissions. basically any air that goes past your air filter has to go out the exhaust thru the cats. that's why modern cars all vent back thru the intake system. the stock BOV going back to the intake has very little to do with keeping the turbo spooled as some would claim. remember, the driving force is the exhaust flow which is the other end of the turbo.
here's how it could hurt performance.
the ecu accounts for the air going in, when a BOV vents to atmosphere the car will run a little rich and sometimes the car will hesitate, stumble or shoot flames. all are negatives for performance.
here's how it could help.
the BOV is just a basic relief valve to prevent backspinning the turbo. when the throttle plate closes the BOV vents presurized air and then reseats. a bigger and/or faster operating BOV will allow boost to build quicker once you get back on the throttle after shifting. i did experiment with a Blitz BOV versus stock on MR-2 back-to-back at the track and witnessed a repeatable ~0.1 sec improvement in 1/4 mile times just changing BOVs. for the WRX there is a catch....IMO the small opening size for the BOV on the IC is the limiting thing and any aftermarket BOV will do no better than stock unless you're running so much boost that the stock BOV isn't holding it.
my $0.02
first off the main reason the stock valve vents back to the intake is emissions. basically any air that goes past your air filter has to go out the exhaust thru the cats. that's why modern cars all vent back thru the intake system. the stock BOV going back to the intake has very little to do with keeping the turbo spooled as some would claim. remember, the driving force is the exhaust flow which is the other end of the turbo.
here's how it could hurt performance.
the ecu accounts for the air going in, when a BOV vents to atmosphere the car will run a little rich and sometimes the car will hesitate, stumble or shoot flames. all are negatives for performance.
here's how it could help.
the BOV is just a basic relief valve to prevent backspinning the turbo. when the throttle plate closes the BOV vents presurized air and then reseats. a bigger and/or faster operating BOV will allow boost to build quicker once you get back on the throttle after shifting. i did experiment with a Blitz BOV versus stock on MR-2 back-to-back at the track and witnessed a repeatable ~0.1 sec improvement in 1/4 mile times just changing BOVs. for the WRX there is a catch....IMO the small opening size for the BOV on the IC is the limiting thing and any aftermarket BOV will do no better than stock unless you're running so much boost that the stock BOV isn't holding it.
my $0.02
01-22-2004, 12:31 AM
#14
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FOUR REASONS TO GET A BOV:
1 - Driveability
2 - Fuel Efficiency
3 - Boosting Up Applications (Factory valves can leak like a sieve!)
4 - The Noise!
Fitting a blow-off valve that "scares the pants off pedestrians at 50 meters" is a blast ...
But you want a whole lot more than a big noise happening under the bonnet. And this is where GO FAST BITS blow-off valves excel.
They're engineered to produce peak performance under ALL conditions. A blow-off valve comes into play when the throttle is closed suddenly under boost conditions. A poor quality component actually slows acceleration and can cause "compression stall" … causing you to stall at the lights.
But that's the least of your problems. Imagine your turbocharger spinning at 80,000rpm pumping a truckload of air through your inlet pipes at nearly 90 metres per second … then you suddenly close the throttle. The "reverse thrust" forces produced are so huge, you can end up with a damaged turbocharger!
GO FAST BITS Hybrid blow-off valves overcome the problem by venting most of the non-required intake pressure into the atmosphere, while a small portion is vented back to the turbo and airflow meter-enough to stop problems such as excessive fuel use, backfiring and engine shudder at half acceleration.
I hope this info helps! For the record I have the GFB Hybrid set to 100% atomos and have never had any problems out of it and you can tell a lot less lag in the turbo in btw. shifts because you are not having so much reverse thrust pressure slowing down your turbo.
Let me know if I can help anyone!
Brian
Flash N Dash Performance
1 - Driveability
2 - Fuel Efficiency
3 - Boosting Up Applications (Factory valves can leak like a sieve!)
4 - The Noise!
Fitting a blow-off valve that "scares the pants off pedestrians at 50 meters" is a blast ...
But you want a whole lot more than a big noise happening under the bonnet. And this is where GO FAST BITS blow-off valves excel.
They're engineered to produce peak performance under ALL conditions. A blow-off valve comes into play when the throttle is closed suddenly under boost conditions. A poor quality component actually slows acceleration and can cause "compression stall" … causing you to stall at the lights.
But that's the least of your problems. Imagine your turbocharger spinning at 80,000rpm pumping a truckload of air through your inlet pipes at nearly 90 metres per second … then you suddenly close the throttle. The "reverse thrust" forces produced are so huge, you can end up with a damaged turbocharger!
GO FAST BITS Hybrid blow-off valves overcome the problem by venting most of the non-required intake pressure into the atmosphere, while a small portion is vented back to the turbo and airflow meter-enough to stop problems such as excessive fuel use, backfiring and engine shudder at half acceleration.
I hope this info helps!
For the record I have the GFB Hybrid set to 100% atomos and have never had any problems out of it and you can tell a lot less lag in the turbo in btw. shifts because you are not having so much reverse thrust pressure slowing down your turbo.Let me know if I can help anyone!
Brian
Flash N Dash Performance
