where should i weld my bov

[franciscoescn]

I just got a new bov from SYNAPSE its the synchronic bov. My question is where should i weld it on the cold pipe or the hot pipe because i heard that its better on the cold pipe. I have my old cheapass greddy rs bov on the hot pipe.

[neox.286]

coldpipe
minimum of 20 inches from the throttle body

[franciscoescn]

Whats better about the cold pipe beside it been cooler

[neox.286]

honestly, I wouldn't know the answer to how they would differ in sound

[StealthWyvern]

Personally I would think you would want it on the hot pipe becuase idealy you wouldn't want to loose the air thats already cooled by the IC.

P.S. I don't know to be honest as I dont know much about the entire turbo gig. It just makes more sence to me logicaly.

[neox.286]

to tell you the truth I honestly dont think it would really matter which pipe you ran it off of....neither really have advantages or disadvantages

as long as the valve does its job is all that really matters haha

[SeR_Cyclops]

they put it on the cold side so when your under boost and you let off the gas it vents the pressure that would have been forced back through the turbo known as compresser surge.

[neox.286]

yea, but it would do the same thing on the hot pipe too

[turbolife]

If recirculated, the cold-pipe is the best choice due to its close proximity to the intake piping.

[neox.286]

good point!

[turbolife]

Also, the cold pipe is better for performance as well.

The shorter the vac line going to the BOV/BPV, the faster the response (it should also be a dedicated vac line). Generally, on our car, somewhere on the cold-pipe will be closer to a suitable vac source than the hot-pipe.

[franciscoescn]

ok guys i ended up welding it on the hot pipe because thats where i had my old one and turnd the car on and it stalled. Do I have to adjust it or what because i also got a check engine light on.

[MREDDLE]

Personaly I would put it on the "hot" pipe as close to the turbo as possible because the main reason we use a BOV is to save the turbo. BOV saves turbo, Wastgate save motor. But this is just my two cents.

[bstdtimsp]

best over all setup is the dual set up you want a 50/50 set up faster spool plus gas get released im going to do the dual set up next

[turbolife]

best over all setup is the dual set up you want a 50/50 set up faster spool plus gas get released im going to do the dual set up next

Please explain how recirc will get faster spool?

[neox.286]

no, it doesnt...

all that 50/50 does it help reduce the turkey noise from compressor surge

[bstdtimsp]

Please explain how recirc will get faster spool?

gases from the recirc valve get forced back into the intake adding more volume to the air in the intake during shift so there is more pressure in the intake chamber

[bstdtimsp]

Please explain how recirc will get faster spool?
double post

[neox.286]

yes recirc is better, which doesnt matter which pipe you are on, but you werent saying recirc....you were saying dual bov setup, which will not affect spooling at all

recirc also wont change your spooling that much at all to tell you the truth, people can argue that point, but the truth is it doesnt make any of a difference because when you blow off by the time that turbo even begins to start spooling again that air has already gone through that turbo and is on its way to the throttle body...

it would if the filter pipe was a pressure pipe, but its not

[speed5hornet]

what about for stalling purposes/moving the maf? then should bov be placed on cold pipe with maf behind it(in between bov and throttle body?)

[neox.286]

I personally never had stalling issues without the relocated maf/recirc, but that depends on the bov...I was running an HKS SSQV, most with that issue were running the GReddy

but the truth is if your making hardpipes, relocate the maf to 20" from the throttle body....it works WONDERS

and it wouldnt matter where the bov was with that setup either as long as its before the maf sensor on the way towards the throttle body

[bstdtimsp]

yes recirc is better, which doesnt matter which pipe you are on, but you werent saying recirc....you were saying dual bov setup, which will not affect spooling at all

recirc also wont change your spooling that much at all to tell you the truth, people can argue that point, but the truth is it doesnt make any of a difference because when you blow off by the time that turbo even begins to start spooling again that air has already gone through that turbo and is on its way to the throttle body...

it would if the filter pipe was a pressure pipe, but its not

well you can argue that as well but from my personal experience dealing with race teams and there set up i will never go just vent to atmosphere either 50/50 or recirc. there are alot of things that go into play with our cars you wont feel that much power but wiht a race car or high horse power car you can tell the difference.

[mspHtown]

well you can argue that as well but from my personal experience dealing with race teams and there set up i will never go just vent to atmosphere either 50/50 or recirc. there are alot of things that go into play with our cars you wont feel that much power but wiht a race car or high horse power car you can tell the difference.

just out of curiosity, what race teams do you deal with?

[bstdtimsp]

just out of curiosity, what race teams do you deal with?

i have worked with gst motorsports, esx motorsports, dyno comp's time attack car, edo performance time attack sti. I worked for power enterprise usa our japanese head quarters supplied the injectors, timing belt, drive belts, and head gasket for the cyber evo.

[jeffmsp]

look at it like this.

1. Placing a bypass valve on the cold pipe will create lower initial intake temperatures. When air is compressed it is heated. Why would you want to blow the hot air from your hot pipe into the turbos intake. The reason mazda did it i am sure was to reduce cat light off time as the hotter the intake temps the sooner the fuel will begin to atomize properly in the intake manifold etc. Run some compression formulas out and you will see what I am talking about. If you are going to go through the effort of intercooling it, you might as well reuse your cooler, denser air.

2.

A turbocharger that is surging will have less lag then one that is not. It will however endure more stress on its internals. I would say a bov is more of a protection mod then a performance mod. Think of a WRC car, they wouldnt run any sort of valve, they will just switch the turbo if it actually wore out during the competition. Not to mention the anti-lag ran throughout the course. Those crews can swap a transmission in less then 30 mins easy, think about how long a turbocharger would take and their budget..

3. I was the first guy to do the 50/50 bov/bpv thing. I played with it alot and it really isnt that great compared to swapping the maf to the pressurized side of the intake system. It will work, but in the end I found it not worth the hassle, messy engine bay, two of something for nothing kinda thing. Especially if you are unflashed ecu.

[mspHtown]

look at it like this.

1. Placing a bypass valve on the cold pipe will create lower initial intake temperatures. When air is compressed it is heated. Why would you want to blow the hot air from your hot pipe into the turbos intake. The reason mazda did it i am sure was to reduce cat light off time as the hotter the intake temps the sooner the fuel will begin to atomize properly in the intake manifold etc. Run some compression formulas out and you will see what I am talking about. If you are going to go through the effort of intercooling it, you might as well reuse your cooler, denser air.

2.

A turbocharger that is surging will have less lag then one that is not. It will however endure more stress on its internals. I would say a bov is more of a protection mod then a performance mod. Think of a WRC car, they wouldnt run any sort of valve, they will just switch the turbo if it actually wore out during the competition. Not to mention the anti-lag ran throughout the course. Those crews can swap a transmission in less then 30 mins easy, think about how long a turbocharger would take and their budget..

3. I was the first guy to do the 50/50 bov/bpv thing. I played with it alot and it really isnt that great compared to swapping the maf to the pressurized side of the intake system. It will work, but in the end I found it not worth the hassle, messy engine bay, two of something for nothing kinda thing. Especially if you are unflashed ecu.


i thought 505zoom was teh first to do the 50/50 setup

[turbolife]

recirc also wont change your spooling that much at all to tell you the truth, people can argue that point, but the truth is it doesnt make any of a difference because when you blow off by the time that turbo even begins to start spooling again that air has already gone through that turbo and is on its way to the throttle body...

That's my take too.


gases from the recirc valve get forced back into the intake adding more volume to the air in the intake during shift so there is more pressure in the intake chamber

Yeah, but the intake isn't under pressure...so there is no pressure in the intake chamber for the recirculated air to add to. As soon as that air gets to the intake, it expands.

I know many subscribe to the "recirc=faster spool", but I don't see it. Show me proof otherwise I have to raise the flag.
Recirculated or VTA, when you close the throttle the BOV opens and releases pressure from the charge pipes. This allows the turbo to not slow down violently due to reversion, which will cause it to pull some air in through the intake (because it is still spinning).

If you recirc, the blown-off air goes back into the intake tube (pre-compressor) to get compressed again. How does that make for faster spool? You are still recompressing the same amount of air, you don't "save" any work vs. a VTA setup.

If I am looking at this wrong, someone please explain...

Also, as a side note, at least one of those race teams mentioned VTA judging by pictures on their website...

[turbolife]

A turbocharger that is surging will have less lag then one that is not.

Not true.

Compressor surge, by definition, is the abrubt reversal of flow through the turbo. This slows the turbo down, which then requires more energy to re-spool to slowed down turbo. Had that turbo not surged, and spun freely, it would not need that excess energy to re-spool.

Am I missing something?

[bstdtimsp]

some of those teams yes may use a vta bov i never said they didn't just my experience and their suggestions on the msp is 50/50. I ran relocated maf with an apexi twin chamber and i wasn't satisfied i had really rough idel then i switched to 50/50 and it evened it out again and i felt a lil less lag now im back to recirc and couldn't be happier

[turbolife]

some of those teams yes may use a vta bov i never said they didn't just my experience and their suggestions on the msp is 50/50. I ran relocated maf with an apexi twin chamber and i wasn't satisfied i had really rough idel then i switched to 50/50 and it evened it out again and i felt a lil less lag now im back to recirc and couldn't be happier

Ahh, you inferred they all recirc'ed. Maybe I misunderstood.

Either way, glad your setup works well for you!

[bstdtimsp]

i never said that they all use recirc valves and yes some probably vta but through my experience and talking with them about my car and set up recirc is recommended. I had the maf moved to the cold pipe with an apexi twin chamber bov and had alot of lag and when i switched to 50/50 that decreased alot

[turbolife]

Recirc will always be recommended for our cars due to it being a MAF setup.

You didn't like your MAF relocated? I haven't heard any negative reviews about it, good to know.

[steedspeed]

ok guys i ended up welding it on the hot pipe because thats where i had my old one and turnd the car on and it stalled. Do I have to adjust it or what because i also got a check engine light on.

Your valve is open at idle so it is bypassing the MAF sensor.

[turbolife]

Why is his valve open at idle?

[neox.286]

because he hasn't adjusted the valve likely

[turbolife]

because he hasn't adjusted the valve likely

Ahh...duh. I am so smart, s-m-r-t, doh! lol

[neox.286]

lolz

[WIMSPWI]

so i am running a turbo xs diverter valve in the factory spot (recirc). if i put my hks ssqv on my hot pipe in front of the exhaust mani will that work fine? i just want the sound of the ssqv while keeping the turboxs for recirculation. and the flange i have fits around my hotpipe perfectly so i really would like to use it there. but i'd have to grind it a bit to fit my intake pipe. any info is greatly appreciated

[dragtillidie]

cold pipe is the best...Its after the intercooler so the air is denser...it will be louder and do a better job. I've heard of numerous people on here still having the turkey with a BOV on the hot pipe. Got mine on the cold with the dual setup and I love it. Just my 2 cents.

[neox.286]

yea, plus you can get a recirc fitting for the HKS btw

SU sells it...I personally used it for a while, worked great

[alexB]

yea, but it would do the same thing on the hot pipe too

No cause it would have to go back thru the turbo to get to the hot pipe.

[neox.286]

uhm...

what??

seriously, rethink what you just typed....the hotpipe is post turbo still....it goes from the turbo outlet to the intercooler, if you have the BOV on that pipe it is exactally the same as if it is on the coldpipe (intercooler -> throttle body)

[alexB]

uhm...

what??

seriously, rethink what you just typed....the hotpipe is post turbo still....it goes from the turbo outlet to the intercooler, if you have the BOV on that pipe it is exactally the same as if it is on the coldpipe (intercooler -> throttle body)

Yeah my bad. I dont know what I was thinking. I would still put it on the cold pipe. It would be too far away in my opinion on the hot pipe. I have mine on my cold pipe with my mafs relocated. Work good.

[turbolife]

uhm...

what??

seriously, rethink what you just typed....the hotpipe is post turbo still....it goes from the turbo outlet to the intercooler, if you have the BOV on that pipe it is exactally the same as if it is on the coldpipe (intercooler -> throttle body)

Yup.

[neox.286]

lol

I gotta agree with you though....the cooler the air the denser the air, Id rather be venting the denser air out of the pipes than the least dense air, my setup is like yours

[dragtillidie]

exactly