CAN i run a BLOW OFF VALVE safely??????

IF I run a atmospheric blow off valve instead of a recycling diverter valve on my 1990 saab 9000 cd 2.0 turbo will it not run as well? will the check engine light appear? has someone done this and can tell me how it runs? I hear it is not good for the ECU and will not spool up as fast. If it is ok which one is the best out there for the $$? i really like the sound of the blow off valves:)

and why is it that i only get boost when the car is in gear and going but not when i just rev it????

Reply to
es
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in article snipped-for-privacy@g49g2000cwa.googlegroups.com, es at snipped-for-privacy@yahoo.com wrote on 22/05/2005 04:54:

You can, but it must be a double piston type valve like the Forge Motorsports FMDV004 or Baileys DV26. Being a closed loop FI system, you will get a slight richness when the valve "blows", but it won't be noticeable in practice apart from quickly letting off the gas in higher gears; there's a slight stumbling feeling.

You won't get any benefit, other than the sound ... Which might not be becoming of a lofty CD :)

Paul

1989 900 Turbo S
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Reply to
Paul Halliday

Why not install an electronic BOV sound effects unit instead? They have the advantage of having an adjustable volume control and you don't even need a turbo charger.

You could also consider putting blue LEDs on your windscreen wipers and replacing your headlamp bulbs with ones that have a blue/green tint.

Revving the engine in neutral will not generate much boost because there is relatively very little air going through the motor without a proper load.

If your car has a slushbox, you could try putting it in gear, standing on the brakes with your left foot and then rev it using WOT to the torque convertor's stall point. When you reach the stall speed don't keep it there too long as your box is gunna get hot real quick. (You know you're at torque convertor's stall speed because the motor won't increase its revs any more)

The technique for a manual is a variation of this but it requires dexterity that you may not yet posess. Put it in gear. Use your heel to hold down the accelerator pedal and use the upper part of your foot to stand on the brakes and at the same time release the clutch sufficiently to load up the motor and allow some slippage. Now you have the conditions for boost. Increase the throttle to WOT and judiciously let the clutch out a bit more to load up the engine (don't forget to keep holding the brakes on). When you see the boost gauge climb and the tacho reaches approx 3,000 RPM release the clutch suddenly while simultaneously releasing the brakes. You should be rewarded with generous amount of wheelspin, torque steer and smoke.

Strangely, privately owned and registered Saabs don't like this treatment. Rentals LOVE it.

Reply to
ShazWozza

LOLOLOL your joking right???

Reply to
es

Are you? What is the point of a "blow-off" valve when your car is already fitted with one that doesn't make noise?

Looking for some bling? I suggest moving to a Honda.

-Fred W

Reply to
Malt_Hound

first of all the one i got right now is leaking because of the boost i am running so i need one that can handle the boost.

and yes i do like the sound of a blow off valve is that such a bad thing lol

Reply to
es

in article snipped-for-privacy@o13g2000cwo.googlegroups.com, es at snipped-for-privacy@yahoo.com wrote on 23/05/2005 15:02:

Really? Just buy another one. 25 quid from the dealer. I know of a 9000 that's over 300 BHP that still uses the original dump valve. Yes, they break/split, but they do hold the boost.

Each to their own. I have a Forge FMDV004 on my C900. You'll need a bung as well to close off the re-circ hole.

Paul

1989 900 Turbo S
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Reply to
Paul Halliday

You can get Forge/Bailey alloy recirc valves using spring/pistons instead of diaphrams that split. They replace the original.

Nope, if that is what floats your boat, go for it. I did on my Celica GT4, because that didn't have any Dump valve/BOV/Diverter fitted at all.

Even with a recirc fitted, if you lose the airbox and fit a cone filter/induction kit, you will hear the turbo spooling and the recirc valve dumping far more, without being overly loud. Just make sure you duct in a good cold air feed, to make sure it doesn't just suck in hot enginebay air.

Reply to
Sleeker GT Phwoar

i do have a cone filter as of right now and it sounds nice but i dont really like the flappy sound of the stock bosch valve so if i get a new high performance diverter valve will i get that tight 'pshhhtt' sound but just not as loud.because that is all i need. if not i can just get a BOV but get an adapter so it goes back into the intake pipe right?

and where can i get a good pirce on these valves??

Reply to
es

Forge are the prefered Valve. You won't get the solid "Pttsch", more a slightly sharper "Tscch" sound than the standard bosch cough.

Depends where in the world you are.

Ebay can be quite good for these kind of things if you go through a trader from the far east.

Reply to
Sleeker GT Phwoar

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