BOV ON HOT PIPE OR COLD PIPE?

[nissan_love]

SO I WANT TO PUT A BOV ON MY CAR I WAS AT A SHOP TODAY AND THEY SAID PUT IT ON THE COLD PIPE BUT ALMOST EVERY PIC THAT I LOOK AT OF A S14 THAT HAS ONE ITS ON THE HOT PIPE CAN SOMEONE PLEASE TELL ME Y???

[White Comet]

search for it and stop using caps

[nissan_love]

i tried search could not find anything

[moulton712]

seen them on both. there are pros and cons.

pro of being on cold side: the bov sees colder air, making the diapham last longer.but then you cant run a recirculating bov, has to be atmospherical.

if your going to want less problems, run it on the hot side and recirculate the bov. tuning, car not falling on it's face, oil temp/pressure, etc.

this is all unless you have an atmospherical bov, then run it on the cold side.

[articzap]

I've read all of the theory, and will only put it in on the hot pipe.

EDIT: In reply to the poster above me, diaphragms suck. Get a BOV that doesn't have one.

[Zetec]

but then you cant run a recirculating bov, has to be atmospherical.

.

Then why does the RB25 run a recirculating bov on the cold pipe from the factory?

[Jadesr20det]

be a baller put it on the cold pipe..get urself some tuning (or an afc or go all out and convert to map sensor) and the car will not stall....ive had ,y sr running for years w/the bov on the cold side and havent had any issues...its better

[moulton712]

you can but there is an issuse of room. running piping back before the innercooler

if you look at the stock rb25 the intake manifold's inlet goes across the top of the motor. it's designed to have the two pipes sort of close to each other. in the typicaly sr setup the hot/cold pipes are on the opposite sides of the motor bay. this is where space becomes an issue. to get a pipe to go back across the motor bay to dump off.

[nissan_love]

thanks guys

[lucky7]

mine is on the cold pipe. but i have EMS and running map.

[bestint]

Blow Off Valve Placement

Blow off valve placement is not the most important thing to think about when building a turbo kit, however is does make a difference. It's the small differences that separate an event winner from the rest of the field.

The vast majority of people will tell you that you are supposed to place your blow off valve within a couple feet of your throttle body. I am here to tell you that this is not the best location for your blow off valve.

The best location for your blow off valve is going to be in between your turbo and intercooler, on the hot side.

Think about it. If you put the blow off valve on the cold side (after the intercooler), you are pushing hot air through your intercooler for nothing. This increases the speed at which your intercooler and motor become heat soaked.

By putting the blow off valve before, or even on the intercooler itself - you allow all of the hot compressed air to escape to atmosphere prior to passing through the intercooler. A blow off valve does the same thing no matter where you place it on the charge piping. Knowing this - it's only logical to put it in a place where it relieves hot air rather than cold air.

[sommmatt]

TYPING IN ALL CAPS IS SO COOL I DON'T KNOW WHY I DON'T DO IT ALL THE TIME.

ANYWAY CONTRARY TO THE ABOVE POSTER'S POST PLACEMENT OF THE BLOW OFF VALVE REALLY MEANS ABSOLUTELY NOTHING. IF YOU RELIEVE THE COLD AIR, AIR STILL HAS TO TRAVEL THROUGH THE INTERCOOLER MAKING NO DIFFERENCE IN ENGINE HEATSOAK. IF THE CAR IS IN MOTION YOU WONT BE HEATSOAKING THE INTERCOOLER ANYWAY (PROVIDED IT IS AN APPROPRIATE SIZE AND PLACEMENT).

YOU SHOULD PLACE THE BLOW OFF VALVE SOMEWHERE IT IS EASILY ACCESSIBLE FOR MAINTENANCE, OR OUT OF THE WAY OF OTHER COMPONENTS.

IF YOU'RE REALLY CONCERNED, PUT ONE ON EITHER SIDE, GET THE BEST OF BOTH WORLDS AND COMPLETELY REMOVE CHANCES OF COMPRESSOR SURGE.

[slidestyle69]

Blow Off Valve Placement

Blow off valve placement is not the most important thing to think about when building a turbo kit, however is does make a difference. It's the small differences that separate an event winner from the rest of the field.

The vast majority of people will tell you that you are supposed to place your blow off valve within a couple feet of your throttle body. I am here to tell you that this is not the best location for your blow off valve.

The best location for your blow off valve is going to be in between your turbo and intercooler, on the hot side.

Think about it. If you put the blow off valve on the cold side (after the intercooler), you are pushing hot air through your intercooler for nothing. This increases the speed at which your intercooler and motor become heat soaked.

By putting the blow off valve before, or even on the intercooler itself - you allow all of the hot compressed air to escape to atmosphere prior to passing through the intercooler. A blow off valve does the same thing no matter where you place it on the charge piping. Knowing this - it's only logical to put it in a place where it relieves hot air rather than cold air.

Wow dude thats a good point. Did you really think of all that all by yourself?

Yea good try...poser

http://www.dragsource.com/inde...iew=7

[ZootedS13]

i see what you did there.....

[kouki munster]

Oh look, I have an s14 and my bov is on the cold pipe.



Seriously people, put the bov where ever you have the free space to put it.

[silverkaturbo]

Blow Off Valve Placement

Blow off valve placement is not the most important thing to think about when building a turbo kit, however is does make a difference. It's the small differences that separate an event winner from the rest of the field.

The vast majority of people will tell you that you are supposed to place your blow off valve within a couple feet of your throttle body. I am here to tell you that this is not the best location for your blow off valve.

The best location for your blow off valve is going to be in between your turbo and intercooler, on the hot side.

Think about it. If you put the blow off valve on the cold side (after the intercooler), you are pushing hot air through your intercooler for nothing. This increases the speed at which your intercooler and motor become heat soaked.

By putting the blow off valve before, or even on the intercooler itself - you allow all of the hot compressed air to escape to atmosphere prior to passing through the intercooler. A blow off valve does the same thing no matter where you place it on the charge piping. Knowing this - it's only logical to put it in a place where it relieves hot air rather than cold air.

I cant believe someone revived a 2 yr old thread just to plagiarize what could very well be the worst article about bov placement, ever. So Im forced to chime in. While bov placement is mostly opinion and personal preference, that article shows some of the worst.

What is the reason for a bov again?? To be obnoxious and grab the attention of the people walking down the street or driving next to you?? No? Oh yea, to prevent compressor surge. And what is the best way to do that? Keep the air moving through the turbo in the same correct direction.

If you put your bov closer to the turbo, you will have more cool air rushing TOWARDS the turbo from the suddenly closed throttle body side than hot air from the turbo side. While the valve SHOULD let most negative flowing air out before pushing into the turbo, the idea of any airflow in this direction is generally not good for preventing compressor surge. Also speaking of your wasting intercooler use comment, this seems worse. You are cooling the air just for it to turn back around and let back out. To make matters worse, any air that didnt make its way through the bov before the throttle opened back up has to change direction once again to head back towards the motor, which cant help the already known lag problems between shifts with bovs.

So put it coldside like kouki munster. His setup has maybe 6" of possible reverse flow direction. This leaves everything pre bov to flow towards the engine, away from the turbo, which will keep your turbo spinning the correct direction between shifts, which may also reducing some lag. If you plan on recircing and dont want the hassle plumbing, put it hotside then. Thats where every intercooler kit with a built on flange ends up putting them anyway. These 2 reasons are exactly why mine is found hotside.

Best article found on the subject. He explains it better.http://www.modified.com/tech/0....html

[bestint]

Wow dude thats a good point. Did you really think of all that all by yourself?

Yea good try...poser

http://www.dragsource.com/inde...iew=7

haha, i never said i thought of it myself. i saw a question, googled it for info and posted what i found. as a great character once said, "why so serious?"

[OM3GA]

LOL mine will be on the spicy side

[sliddinsil8o]

AND NOW HE IS DEAD!!!!!!!!!

[scotty-2-forty]

Both ... ... but I'm high HP/TQ and running MAF'less and a stand-alone EMS.