i was just wondering if it made a big deal or not, everypic i've seen of peoples
it was always after the intercooler close to the throttlebody is this nessasary or can
you basically put it where you want it, i was thinking i could put it before the intercooler
about a foot away from the turbo, good idea or no ?

 

It's usually recommended to put the BOV about 2 feet away from the throttle body (TB).

Once the TB closes, all that compressed air needs to go somewhere and right smack dab between the TB & turbo seems like a pretty good place. Some intercoolers even have a BOV built in!

 

Here's some info/opinion: http://sohchonda.com/ipw-web/bulleti...pic.php?t=6684

 

thank you for your post but i think i know all that already, my question was can i
put it befor the intercooler

 

u can put it where ever you want between the turbo and tb, ANYWHERE

 

you can put it anywhere, but its recomended to put it before the IC. I belive this is where rally cars have thiers...its in the book maximum boost, but its not in front of me now.

 

i dont think he cares about efficiency

 

i asked the same ? on another forum a few weeks ago. (civic.indybbs.net) this is what zerodaze had to say:

here is a write up i did a while back about BOV's

enjoy

Let’s take a quick look at the BOV (Blow Off Valve) and what it does for you and your car.

First, a quick history lesson.
Q. Where did the BOV come from, who could possibly have made something that sounds so cool?
A. Porsche, Duh. Developed for there race cars (early 80's i believe) it was patented as a Pop Off Valve. You may still hear some old timers refer to it as such.

There, now you have learned something today, and can wow your drunken friends at the bar.

Ok, let’s take a look at what this little gizmo does.
The BOV releases the pressurized air from the intake pipes when you lift your foot off the throttle; either to shift, or just to hear the cool sound.

Now, why do we need to do this? To taunt others in to racing? Just because it sounds cool? Possibly, who knows with those Germans, those may have been underlying reasons. Actually the intended purpose was actually for performance.

When you lift your foot the throttle plate closes, and that air bounces off the throttle plate and makes it way back towards the turbo. When that air gets back to the turbo it will try to spin it backwards (compressor surge).
Now when you reopen the throttle the turbo has been slowed, or even stalled, and needs to be reaccelerated. With a BOV in place, this air would never make its way back to the turbo, and the turbo would be able to continue spinning freely. Now when you get back on the throttle your turbo is still spinning from before, and will spool more quickly.

Lets take a look at BOV placement.
Some will argue that it should be near the throttle body, others say closer to the turbo.
Well, lets look where Porsche put it on their race cars.
Porsche made the BOV part of the compressor housing, and redirected the compressed air to the turbo inlet. Pretty slick, huh?
I am from the close to the turbo camp, and i will explain why.
1. The air doesn’t just bounce back off of the throttle plate, there are sharp bends in the pipe, and a giant obstruction called an intercooler in the way. 2. By placing it near the turbo you vent only the air that has made it back to the turbo, leaving the rest of the pipe with some pressurized air still in it.
3. Having the BOV after the intercooler vents air the ic has already cooled. Kind of a waste, dont ya think?

Placing the BOV near the throttle body seems to be out of ease. Just like the boost pressure reference nipple being on the turbo housing. (We all know pressure in the housing is not the pressure in the manifold) It was just easier, and less costly that way.

Now i am sure you have been reading this and saying to yourself "Hey, i thought the BOV was to keep the turbo from getting surge and damaging it." It does do that, but that was not its original intent.

And that my friends is the BOV and you.

 

where ever you feel the need