Read this before you create a new thread about BOVs (Blow-off valves) - Page 5

EESTI · 01-28-2008, 12:22 PM

Quote:

Originally Posted by EESTI

I have a few further questions. Is anyone running a blow through MAF after the BOV? If so, theoretically it wouldn't matter right?
Also, does a BPV reduce lag between shifts with larger turbo's?

How does the spring rate (15 lb, 7 lb ect) rating in a BPV or BOV compare to your boost levels?

Bump for the question

STINANC · 03-17-2008, 12:00 AM

so my question is that if BOV makes the car run richer, can't I just put on an aftermarket intake for more air to mix with the extra fuel??

psuLemon · 03-17-2008, 04:33 AM

Quote:

Originally Posted by STINANC

so my question is that if BOV makes the car run richer, can't I just put on an aftermarket intake for more air to mix with the extra fuel??

NO.....

***Majin*** · 03-17-2008, 05:11 AM

Quote:

Originally Posted by psuLemon

NO.....

thanks for the post. it was helpful.

because...

the air is metered by the MAF and the BOV dumps the metered air out of the intake system.

this causes the car to run rich between shifts because since the air that was metered by the MAF had the proper amount of fuel added by the ECU, now you're dumping out the metered air (via BOV) and leaving the fuel.

that causes the rich "spike" between shifts.

will your car die from it? no. will it backfire and become less smooth between shifts? yes.

psuLemon · 03-17-2008, 06:05 AM

Quote:

Originally Posted by Majin

thanks for the post. it was helpful.

will your car die from it? no. will it backfire and become less smooth between shifts? yes.

Anytime

I do question your last comment due to experience with friends car. My friend had a 03 wrx.. mods consisted of a BOV and a borla catback. After 20K on these mods, he started to surge a lot between shifts. Needless to say, about 20K after that his car go boom. Those are the only mods that I knew of, so maybe he did something that I didn't know of. But every car reacts different, just keep that in mind. But if you run rich for 50K miles, that can have a major affect on your motor. Sad thing is, I warned this guy repeatily about removing that stupid BOV and he didn't listen...

***Majin*** · 03-17-2008, 06:59 AM

that's a pretty big stretch to relate a car going boom from a BOV. being it wasn't your car and you didn't know what else may have been done to it, it's best not to start another urban legend for the BOV. it was probably something else that caused your friends car to grenade.

i have had a 50/50 venting/dumping BOV on my car for about 25,000 miles and have never had a problem with the engine from it. i have been tuned with it so i know for a fact that i am not running as rich as i did when the car was stock. in fact, the only time you will run rich with the BOV is in between shifts, not all the time. also, a good tuner can help clean that up for you as well.

renns · 03-17-2008, 07:09 AM

How much can a tuner clean up running rich between shifts? I'm debating whether or not to get one with EWG/meth on the stock VF39.

psuLemon · 03-17-2008, 08:34 AM

Quote:

Originally Posted by Majin

that's a pretty big stretch to relate a car going boom from a BOV. being it wasn't your car and you didn't know what else may have been done to it, it's best not to start another urban legend for the BOV. it was probably something else that caused your friends car to grenade.

i have had a 50/50 venting/dumping BOV on my car for about 25,000 miles and have never had a problem with the engine from it. i have been tuned with it so i know for a fact that i am not running as rich as i did when the car was stock. in fact, the only time you will run rich with the BOV is in between shifts, not all the time. also, a good tuner can help clean that up for you as well.

Well i know he wasn't tuned as he always said he needed to get tune sometimes soon. Plus I am sure he didn't play with the settings on the BOV to make it work to its capability. But you can't say it is health or even bright to run something that makes you run rich. You are better off running an intake, especially if you are going to be tuned. It is proven that a car tuned with an intake can produce nice mods. And unless you are running big mods, BOV are just noise that wil make your car run like crap.

As I stated early, his car surged between shifts. None of which happened until after he put on the BOV.

***Majin*** · 03-17-2008, 11:24 AM

Quote:

Originally Posted by psuLemon

Well i know he wasn't tuned as he always said he needed to get tune sometimes soon.

sounds like this was surely the reason for his car's demise.

Quote:

Originally Posted by psuLemon

Plus I am sure he didn't play with the settings on the BOV to make it work to its capability.

there shouldn't be any settings on a BOV/BPV to make it run better. you can ether tighten (or loosen) the spring to allow more/less pressure open the valve to dump the charged air.

Quote:

Originally Posted by psuLemon

But you can't say it is health or even bright to run something that makes you run rich. You are better off running an intake, especially if you are going to be tuned.

not that it's good to run rich or lean, but it's much safer to run richer than leaner as running leaner will increase likelihood of detonation/knock events. you should only put on an intake if you are on your way to getting tuned as fooling with your intake calibration tables is NOT a good idea unless your tuner is doing that for you.

Quote:

Originally Posted by psuLemon

It is proven that a car tuned with an intake can produce nice mods. And unless you are running big mods, BOV are just noise that wil make your car run like crap.

i had to upgrade my BPV because i went with a bigger turbo and was running over 22-23PSI. the factory BPV has trouble holding that much boost unless you crush it, and it wasn't (and still isn't to my knowledge) a science yet, so i didn't want to risk damaging it and not having something exact.

Quote:

Originally Posted by psuLemon

As I stated early, his car surged between shifts. None of which happened until after he put on the BOV.

sounds like the car wasn't happy with the parts it had on it and the ECU was trying to fix it (but could only compensate so much) and was thus unable to put the car back to maximum happiness.

Muffnbluff · 03-17-2008, 04:09 PM

Quote:

Originally Posted by Majin

i had to upgrade my BPV because i went with a bigger turbo and was running over 22-23PSI. the factory BPV has trouble holding that much boost unless you crush it, and it wasn't (and still isn't to my knowledge) a science yet, so i didn't want to risk damaging it and not having something exact.

IMO the stocker is more than capable of boost at those levels. I run the stocker and I peak at about 24psi and taper to 22psi to redline.

***Turbineguy*** · 03-17-2008, 06:33 PM

Quote:

Originally Posted by Muffnbluff

IMO the stocker is more than capable of boost at those levels. I run the stocker and I peak at about 24psi and taper to 22psi to redline.

24psi on my stock valve here as well. I have run it at 26psi and didn't have any issues.

***Majin*** · 03-18-2008, 05:25 AM

at the time i ran 27 PSI tapering to 24 and it was not able to hold.

AndresDiaz · 05-27-2008, 04:48 PM

Quote:

Originally Posted by Siegel Racing

Does this help?

http://www.siegelracing.com/bov.htm

SS

So does this mean that a BOV really does nothing

RayN · 05-27-2008, 10:27 PM

if you just want the wosshh sound, why dont you just pull the recirc hose off? ( and plug it) why spend money on a show off valve when you already have one? where is my stick, i need to go beat a dead horse or something.

psuLemon · 05-28-2008, 03:21 AM

Quote:

Originally Posted by AndresDiaz

So does this mean that a BOV really does nothing

It does do something.....

it makes your car run rich

03-17-2008, 12:00 AM	#62
STINANC Junior STI Driver Car: wht 04 STI Fav Mod: oil change Location: a big empty cubic room Posts: 66 Join Date: Sep 2007 Trader Rating: (0)	Re: Read this before you create a new thread about BOVs (Blow-off valves) so my question is that if BOV makes the car run richer, can't I just put on an aftermarket intake for more air to mix with the extra fuel??

03-17-2008, 06:59 AM	#66
*Majin* A.X.D. Car: 2004 STi Location: LI, NY Posts: 12,792 Join Date: Apr 2004 Trader Rating: (2)	Re: Read this before you create a new thread about BOVs (Blow-off valves) that's a pretty big stretch to relate a car going boom from a BOV. being it wasn't your car and you didn't know what else may have been done to it, it's best not to start another urban legend for the BOV. it was probably something else that caused your friends car to grenade. i have had a 50/50 venting/dumping BOV on my car for about 25,000 miles and have never had a problem with the engine from it. i have been tuned with it so i know for a fact that i am not running as rich as i did when the car was stock. in fact, the only time you will run rich with the BOV is in between shifts, not all the time. also, a good tuner can help clean that up for you as well.

03-17-2008, 07:09 AM	#67
renns Silver Member Car: 04 JBP STi Fav Mod: I do meth... Location: NJ Posts: 437 Join Date: Nov 2007 Trader Rating: (4)	Re: Read this before you create a new thread about BOVs (Blow-off valves) How much can a tuner clean up running rich between shifts? I'm debating whether or not to get one with EWG/meth on the stock VF39.

03-18-2008, 05:25 AM	#72
*Majin* A.X.D. Car: 2004 STi Location: LI, NY Posts: 12,792 Join Date: Apr 2004 Trader Rating: (2)	Re: Read this before you create a new thread about BOVs (Blow-off valves) at the time i ran 27 PSI tapering to 24 and it was not able to hold.

05-27-2008, 10:27 PM	#74
RayN Lurker Car: 05 WRB WRX Location: vegas Posts: 6 Join Date: Jul 2007 Trader Rating: (0)	Re: Read this before you create a new thread about BOVs (Blow-off valves) if you just want the wosshh sound, why dont you just pull the recirc hose off? ( and plug it) why spend money on a show off valve when you already have one? where is my stick, i need to go beat a dead horse or something.