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Discussion Starter · #1 ·
I have a 94 Griffin with a 2.3 Direct Ignition engine. I would like to raise the turbo boost. Can anyone help with suggestions? Where do I find the APC unit on this vehicle?
 

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Trionic incorporates the APC system in with the ECM, so you won't find a box.
You can try adjusting the wastegate rod for more preload, you can buy a manual boost controller, or you can slap down the cash for an ECU upgrade.
 

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Discussion Starter · #3 ·
Thanks

Thanks for your help. I have found a good webpage about adjusting the wastegate rod complete with pictures to make it easy. I will try that. It did not say how much more power to expect so if anyone has been down this road and can give me an idea how much more power to expect and how many turns it is safe to wind the rod end could they write a few line about these 2 things.
 

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94 Griffin said:
Thanks for your help. I have found a good webpage about adjusting the wastegate rod complete with pictures to make it easy. QUOTE]



Could you post a link to that website? I'd like to take a look at it myself. Thanks!
 

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Discussion Starter · #5 ·
Link not working

Sorry it looks like the link is not working but I had saved the information on my computer and have pasted it here for you. If you want the pictures I can email them to you.

Adjusting the basic boost pressure on the Saab 9000
Introduction

The APC system used on all full-pressure Saab 9000 Turbos (although implemented in at least three different ways over the years) controls the turbo boost pressure above a certain level known as basic boost (or base boost). This level of boost is set mechanically by the wastegate actuator on the turbo and should be set to a prarticular pressure, depending on the model. This procedure shows how to measure and adjust the base boost pressure.

Time required

Each adjustment requires only a few minutes. However, if further adjustment is required, the engine must be allowed to cool sufficiently to touch. From my experience, this typically takes a few hours.

Tools required

N.B. These were the tools I found necessary for the TD04 on my manual '96 Aero. Other turbo installations may require different tools.


Spanners
  • 10mm or 11mm, depending on model
Other
  • Boost gauge
    A boost gauge is essential for measuring the base boost level. There is no other way. The more accurate (and precise) the better, but I get good enough results from a gauge that is not very precise (I reckon I can resolve to within 0.05 bar on this gauge, with care - this is just barely enough precision for this task). A gauge with a range of around 0.7 bar (10PSI) will provide best resolution for this task. This is what I use.
    I also have a TIM boost pressure gauge, made in the UK, which has a range of 2 bar. While this is not very precise due to the small scale and large range, I have used it to measure base boost. It is better suited to measurement of peak boost. This gauge is designed to be mounted inside the car, but I only use it for adjustment so I don't have it permanently mounted.
Procedure

The various parts mentioned in this procedure are shown below (Aero with Mitsubishi TD04 turbo shown):




If the basic boost pressure has been lost completely

If the basic boost pressure adjustment has been completely lost, for example the wastegate actuator or turbocharger has been dismantled or replaced, an initial setting may be set as follows:
  1. If necessary, jack up the front of the car and support it on axle stands.
  2. Slacken the locknut on the wastegate actuator rod.
  3. Remove the circlip or spring clip retaining the rod end on the wastegate lever and unhook the rod end from the pivot on the lever.
  4. Unscrew the rod end until the hole in the rod end just slips over the pivot, with the wastegate held in the closed position.
  5. Screw the rod end back in by 3.5 turns. This will pre-stress the actuator by approximately 3mm when the wastegate is closed.
  6. Refit the rod to the wastegate and refit the retaining clip.
  7. Measure the basic boost pressure as described below and adjust if necessary.
Measuring the basic boost pressure
  1. Connect a boost gauge to the car. My '96 Aero has a vacuum takeoff point for just this purpose situated on the inlet manifold. It is normally blocked off by the rubber plug seen in the foreground. Other models may require the insertion of a tee-piece (supplied with the TIM gauge) in one of the vacuum lines. Do not connect to the PCV hose (on top of the cam cover with a white plastic valve halfway along it).

    On non-Trionic cars:
    1. On non-Trionic cars, disconnect the electrical connector on the APC solenoid valve. This is mounted on top of the radiator on the left side of the car (battery side). It has an electrical connector and three rubber hoses connected to it. Don't disconnect the hoses.
      (I don't have a photo of the non-Trionic style of valve. If anyone can supply a photo showing the valve and its location, I will be very grateful).
    2. Take the car for a test drive and with the engine at normal operating temperature, do some hard accelerating. A steep hill can help here.
      Note the maximum boost pressure indicated on the gauge.
  2. On Trionic cars and LPT models:
    1. Take the car for a test drive and with the engine at normal operating temperature, select third gear (manual or automatic) and accelerate at full throttle from below 1500 RPM (avoid the kickdown on models with automatic transmission). As the engine speed approaches 3000 RPM, press the brake while holding the accelerator, to achieve full load at 3000 RPM (pressing the brake pedal also causes Trionic to drop the boost pressure to base boost on non-LPT models). Note the pressure on the gauge.
  3. If the basic boost pressure is not within the specification, adjust it as described below and repeat the measurement.
Adjusting the basic boost pressure










N.B. Perform this operation with the engine cold. Even a few seconds of running can make the turbocharger too hot to touch.
It is best to do this while parked on a hard, even surface (e.g. concrete or asphalt, not grass) to minimise the risk of losing the retaining clip should it spring free suddenly.
  1. If necessary, jack up the front of the car and support it on axle stands.
  2. Holding the wastegate actuator rod near the threaded end with a pair of pliers, slacken the locknut using a 10mm or 11mm spanner. It is important not to hold the rod near the wastegate actuator (the round can) as any slight damage to the rod in that area can cause the rod to bind in the actuator.
  3. Remove the circlip or "R" clip retaining the rod end on the wastegate lever pivot.
  4. Screw the end piece in (shorten the rod) to increase boost pressure or out (lengthen the rod) to reduce it. See the specification for the approximate relationship between number of turns and pressure adjustment. Best performance will be achieved by adjusting towards the upper end of the specification. However, exceeding the specification can cause problems, including the risk of engine damage in adverse conditions.
  5. Replace the rod end on the wastegate pivot and refit the retaining clip. Note that on my Aero, the hole in the pivot for the "R" clip is vertical and it would be much easier to insert the clip from underneath than from above. However, it would then also be much easier for the clip to fall out. I have become practised at inserting the clip from above.
  6. Once again holding the rod with a pair of pliers near the threaded end, tighten the locknut.
  7. Measure the basic boost pressure using the method described above. If necessary, allow the engine to cool and repeat the adjustment.
Basic boost specification for various 9000s

Note: all specifications were originally specified in bar and the conversion to PSI is approximate.

These are the specifications I have been able to find so far. If your car is not listed here and you know what the basic boost pressure should be, I would be happy to hear from you. I'm especially curious about the specification for the rarer, higher-powered 9000s such as the CS Turbo S and the Carlssons.

Model - Bar/PSI Approx. adjustment per full turn
2.3 Turbo (except manual Aero) - 0.03/0.5
Aero (manual) - 0.05/0.75
2.3 light-pressure turbo - 0.03/0.5
2.0 light-pressure turbo ('92-'93) - 0.03/0.5
2.0 light-press. Turbo/intercooler - 0.03/0.5
2.0 Turbo (non-Trionic) - 0.02/0.25

 

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dont adjust the waste gate actuator, as its a very low pressure spring to make any differance you will need to set it too high and then it will not allow the boost to reduce enough at high rpm, if you want more boost get a manual boost controller
 

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Discussion Starter · #9 ·
Thanks Boxman

boxman said:
dont adjust the waste gate actuator, as its a very low pressure spring to make any differance you will need to set it too high and then it will not allow the boost to reduce enough at high rpm, if you want more boost get a manual boost controller
Thanks Boxman. I tried this adjustment last night and all it did was to make the Turbo smoother over a greater rev range. Before I got a kick in the pants for just a short time but now the kick lasts longer. I will try this for a week and if I am not happy then I will put it back as it was. Your comment is correct but at the moment my pockets are short and my arms are long. I will get a manual boost controller when I can afford it.
 

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Be VERY careful with the MBC. It bypasses Saabs great APC system and exposes the engine to potential doom. A little MBC is great - too much a no no.
A proper remap is way better but costs much more.
Adjusting the base boost as above has zero effect on performance apart from making it run correctly (still a worthy thing to have done)
 

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skint said:
Be VERY careful with the MBC. It bypasses Saabs great APC system and exposes the engine to potential doom. A little MBC is great - too much a no no.
A proper remap is way better but costs much more.
Adjusting the base boost as above has zero effect on performance apart from making it run correctly (still a worthy thing to have done)
you will be fine with the mbc....if u have it to high...ull hit fuel cut...then u just turn it down a bit.....trust me
 

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skint said:
Be VERY careful with the MBC. It bypasses Saabs great APC system and exposes the engine to potential doom. A little MBC is great - too much a no no.
A proper remap is way better but costs much more.
Adjusting the base boost as above has zero effect on performance apart from making it run correctly (still a worthy thing to have done)
I havent bypassed the apc system, the mbc is in between the W hose so i still have the apc in use, im close to 13-14 psi

Imran
 

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Posted by 9-3Aero: I havent bypassed the apc system, the mbc is in between the W hose so i still have the apc in use, im close to 13-14 psi
That's the way to do it. And I have 2 additional in-dash boost gauges so I can monitor the pressure from the APC and also the (reduced) pressure from the MBC that is being fed to the wastegate.
 

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I have one additional boost gauge that is coming off the extra vacuum port, next to the port for the stock gauge, Robin what do you mean reduced pressure?

Imran
 

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Discussion Starter · #15 ·
boxman said:
dont adjust the waste gate actuator, as its a very low pressure spring to make any differance you will need to set it too high and then it will not allow the boost to reduce enough at high rpm, if you want more boost get a manual boost controller
Boxman I have done a little research and have found the MBC's are not as expensive as I thought they might be. Can you or anyone else give me a link to a good, easy to connect (good instructions) and safe one?
 

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Posted by 9-3Aero: Robin what do you mean reduced pressure?
With the APC connected directly to the wastegate, the wastegate receives whatever pressure the APC is releasing from the "W" port.

However, if you have the MBC between the APC and the wastegate, you can set the MBS to bleed-off a few psi of boost, so that what reaches the wastegate is slightly less than the original APC pressure. So, for a typical setup:

Pressure from APC "W" port........................ = 15 psi
Pressure actually reaching Wastegate.......... = 12 psi
Hence, pressure reduction due to MBC......... = 3 psi
...and thus the wastegate will take a little longer to open fully.

To monitor this, put a boost gauge between the APC and the MBC, and another gauge between the MBC and the wastegate. And it's a good idea to keep the pressure reduction in the range 1-4 psi, else ka-boom! You probably know that rule-of-thumb says 1 psi boost is approximately = 5 HP.

All this became possible when I replaced the radio and CD player with an aftermarket Radio/MP3 unit, and thus freed up a single DIN slot for the boost gauges. It worked fine for the basic car and some early upgrades, but I don't use it with Maptun software that was designed exactly for my car.
 

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Robinb said:
With the APC connected directly to the wastegate, the wastegate receives whatever pressure the APC is releasing from the "W" port.

However, if you have the MBC between the APC and the wastegate, you can set the MBS to bleed-off a few psi of boost, so that what reaches the wastegate is slightly less than the original APC pressure. So, for a typical setup:

Pressure from APC "W" port........................ = 15 psi
Pressure actually reaching Wastegate.......... = 12 psi
Hence, pressure reduction due to MBC......... = 3 psi
...and thus the wastegate will take a little longer to open fully.

To monitor this, put a boost gauge between the APC and the MBC, and another gauge between the MBC and the wastegate. And it's a good idea to keep the pressure reduction in the range 1-4 psi, else ka-boom! You probably know that rule-of-thumb says 1 psi boost is approximately = 5 HP.

All this became possible when I replaced the radio and CD player with an aftermarket Radio/MP3 unit, and thus freed up a single DIN slot for the boost gauges. It worked fine for the basic car and some early upgrades, but I don't use it with Maptun software that was designed exactly for my car.
Yeah man, I would think wrong things about you if you would have stage 5 maptun package and still run MBC:cheesy:lol

Klim
 
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