Plumback Bov Plumbing

[NYTSKY]

Hi all,

I will be fitting a Greddy plenum to my 25 soon and im wondering how will i plumb the BOV back to the intake from the other side of the engine bay?

Do i just get a pipe made from the BOV running along the front of the motor to the intake?

I want to run the BOV on the pipe going into the plenum,im ditching the washer bottle so will be located around that spot.

Looking through some threads i came across this photo.Im assuming this pipe is going from a BOV to the intake.

Should i be doing something like this?

[**RB2530**]

I run that plenum as well...At first I made up a pipe that ran from the intake pipework just before the throttle body going across the front of the motor (like in the picture) but lower, back to the compressor intake pipework...It was 1 1/4" pipe and ran just behind the cooling fan...I then changed this...Now the BOV is connected to the pipe work running to the I/C on the intake side of the engine...Much less pipework...

In my opinion either way works fine, the only difference is, if the BOV is fitted to the hot side of the IC, when it opens it passes hotter air back into the intake...

BUT when running pipework across the front of the engine, the pipe work heats up anyway because it is just behind the radiator so it heats the intercooled air anyway...The air in the plumback pipe is static until the BOV opens and heats up to the pipework temperature...So you dont really win either way

[NYTSKY]

I have been told to keep the BOV as close to the throttle body as possible.

[FineLine]

I have been told to keep the BOV as close to the throttle body as possible.

My bov is mounted under the drivers side Guard and piped back under the car and back up behind the power steering pump.

I dont like the pipe going across the cam cover for looks and heat. Under the car the pipe is at least getting some ventilation.

[**RB2530**]

I have been told to keep the BOV as close to the throttle body as possible.

I'd be interested to know why?

[abu]

Is that your engine bay?

Looks awesome - mega neat!

I'd be interested to know why?

Probably because thats where the pressure comes and stops - but I don't think it would make any difference to were it is

[steven22]

Why not use a gtr approach

[**RB2530**]

Is that your engine bay?

Looks awesome - mega neat!

Probably because thats where the pressure comes and stops - but I don't think it would make any difference to were it is

Yeah understand that although the BOV protects the compressor so based on this you would put the BOV as close to the compressor as possible..plus the air is hotter at the compressor outlet and would flow through BOV easier...

I have seen BOVs fitted to I/C itself as well...

I am with you, I dont think it makes a lot of difference....

[abu]

Yeah understand that although the BOV protects the compressor so based on this you would put the BOV as close to the compressor as possible..plus the air is hotter at the compressor outlet and would flow through BOV easier...

I have seen BOVs fitted to I/C itself as well...

I am with you, I dont think it makes a lot of difference....

Yep agree with you there

Shouldn't make any difference

[gadget1382]

I think it's just a way of keeping the build up of pressure more even into the intake plenum. If it were further back in the pipe scheme it would allow it to spike just that little bit more.

I doubt it makes that much difference, but it probably would help the longevidy of the engine a little.

[GeeTR]

Why not use a gtr approach

+2 - under (or close to) the bottom of the IC.

BOV before or after; I don't think it makes much of a diff either. One could say, that if taken closer to the plenum, then you maintain a flow or slug of air, through the pipe work while BOV's open.

[Bliksem]

I ran mine between the turbo outlet and the intercooler and venting straight back into the intake pipe. I'll try to dig up a pic...

If you fit it closer to the throttle body you would theoretically have to refill the intercooler and piping with new air on each gearchange / venting of bov...

[NYTSKY]

I think ill go underneath,but stay in the engine bay.I dont think it will be affected by heat as much when down low.

Thanks for all your input.Pics would be good if anyone has any.

EDIT: I forgot to add,the turbo will be in a highmount position.