FORGE FMCL007P what spring

[justyjust]

hi peoiple im thinking of upgrading my BOV i have a Saab 9-5 2.3T LPT.
what is the boost pressure on my car standard and stage 1 tune in PSI ?? the model BOV im thinking of getting is a FORGE FMCL007P it comes with a Green spring, what color would i need on standard untuned car??? and what color would i need for stage 1 tune???

Cheers justin

[NickTaliaferro]

Green :) Thats all you need ever.

[SectorNine50]

Just to elaborate on what he said, the orientation of the recirculating valve makes it so the spring doesn't have to actually hold against the boost of the turbo. The green spring, even on Aero's, seems to be plenty. ;)

Correct me if that is wrong Nick.

[stipud]

Bingo. However, if you mount the valve the other way around, you would need the stiffer spring to keep it from leaking boost. This is how most cars have the bypass installed, as it releases quicker this way (the boost will help open the valve).

Also, in some cases it can still leak boost with just the green spring, and some people have needed to shim it with a washer. The yellow spring is probably just fine as well.

[justyjust]

thanks all i have ordered a new forge valve, should be here in a couple of days. what would be the signs of boost leakage?? you know the control valve that connects up the the turbo and actuator the pipe that leads to the turbo had gotten damaged and i had to cut some off, what size silicon hose would i need to replace it????

cheers justin

[MNRO57]

Can someone please explain to me exactly how the BPV actually works. I am about to order the Forge FMCL007P valve. if the green spring is rated at 5-15psi, when is boost released. Can you also tell the the factory boost level for the 2004 9-5 Aero has. I have investigated and read on the ointernet that it produces a max 1.4bar at the higher rev range. Can someone please advise if the factory boost of 1.4 is correct and the green spring is all i need according to this forum how does it work. I am new to turbo as the aero is my first Saab. I have searched in the forum for my answers but to no avail. I know theres alot of questions here but any info would be great.

[SectorNine50]

Can someone please explain to me exactly how the BPV actually works. I am about to order the Forge FMCL007P valve. if the green spring is rated at 5-15psi, when is boost released. Can you also tell the the factory boost level for the 2004 9-5 Aero has. I have investigated and read on the ointernet that it produces a max 1.4bar at the higher rev range. Can someone please advise if the factory boost of 1.4 is correct and the green spring is all i need according to this forum how does it work. I am new to turbo as the aero is my first Saab. I have searched in the forum for my answers but to no avail. I know theres alot of questions here but any info would be great.
The BPV works off of the engine's vacuum system. When your off the gas, it creates vacuum behind the throttle body as the cylinders try to suck in more air than is available due to the throttle body being closed. This then sucks air though those vacuum lines to the BPV. So when you let off the gas, the vacuum runs through the lines, and pulls that valve open to release the excess pressure from the delivery pipes. The spring basically is just there to keep the BPV closed when under boost.

On these cars, the green spring is plenty due to the orientation of the BPV. Since the BPV's piston faces away from the boost pressure, the spring doesn't have to work nearly as hard to keep the BPV closed under boost.

Long story short, green spring is the spring for you! :cool:

P.S. The Aero's max boost can run from 15 psi boost to 17 psi boost (this is from experience)

[SectorNine50]

thanks all i have ordered a new forge valve, should be here in a couple of days. what would be the signs of boost leakage?? you know the control valve that connects up the the turbo and actuator the pipe that leads to the turbo had gotten damaged and i had to cut some off, what size silicon hose would i need to replace it????

cheers justin
I believe they are 4mm.

Check out GenuineSaab.com, they have silicon piping on their site that is the correct size.

[MNRO57]

Thanks SectorNine50 (http://www.saabcentral.com/forums/member.php?u=14968). Greatly appreciate it. Once I replace the BPV, is it a good idea to replace all vacuum hoses or just the hose going to the BPV. What effect would be done if you place the green spring adding extra shims. In your experience which brand is the more reliable ecu tune. There is np one in australia that does Hirsch, I can get Abbott, BSR, Speedparts or Maptun here in Aus. vbmenu_register("postmenu_1431493", true);

[SectorNine50]

Thanks SectorNine50 (http://www.saabcentral.com/forums/member.php?u=14968). Greatly appreciate it. Once I replace the BPV, is it a good idea to replace all vacuum hoses or just the hose going to the BPV. What effect would be done if you place the green spring adding extra shims. In your experience which brand is the more reliable ecu tune. There is np one in australia that does Hirsch, I can get Abbott, BSR, or Maptun here in Aus. vbmenu_register("postmenu_1431493", true);
Unless you suspect your vacuum hoses are cracking or leaking, there shouldn't be a reason to replace them. I run my Aero on the green spring without any shims. I suppose if you added them it would just take more pressure to open up the BPV which in turn would delay or slow it's opening. I'd only up the spring pressure if you are having trouble holding boost, which I doubt will be an issue.

This is one of the biggest questions of the forum, and unfortunately, there isn't a solid answer as they all are said to be reliable from their users. Abbott (http://www.abbottracing.com) and Maptun (http://www.maptun.com) are well known Saab tuners while BSR (http://en.bsr.se/) works with many different types of cars including Audi, Porsche, VW, Skoda, Saturn, Volvo, Opel, and Seat. In spite of the fact that they are not Saab specialists, their users still tend to give good reviews. The PPC system BSR uses is quite clever, removes the need for an ECU exchange or an on-site tune which simplifies the process for many people.

However lets try to keep this thread on topic. Try doing a forum search and see what other users have to say, if you still have questions create a thread in the 9-5 Performance forum or PM me.