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Ok soi finally got round to plumbing a gauge.

Taken direct from inlet manifold, nothing between that and gauge bar the finest silicone hose

Car: Saab 9-5 2.3 lpt auto, with speedparts stg2.

Heres my readings..

At idle out of gear -0.7bar
At idle in gear -0.5bar
On overrun -0.6bar
At WOT +0.5bar

To me WOT reading appears low??
Also, would not fitting bushed piece make difference, aprt from the chatter I'm getting? (I know I should've listened and put it in, but it's not the end of the world!)

[ 10.11.2003, 17:22: Message edited by: Leon [9-5 stg2] ]
 

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Hmmm... it certainly sounds low on WOT. I'd have expected at least 0.9 bar.

Remind me (and others) about the bushed piece?

[edit] read the other post... the bush is to restrict the flow rate to avoid oscillations, so it certainly won't be having a negative effect not fitting it

[2nd edit] I'd try getting hold of the pukka Saab test gauge and try it to see if it agrees.
 

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Originally posted by Mark E:
[qb]Hmmm... it certainly sounds low on WOT. I'd have expected at least 0.9 bar.

Remind me (and others) about the bushed piece?

[edit] read the other post... the bush is to restrict the flow rate to avoid oscillations, so it certainly won't be having a negative effect not fitting it

[2nd edit] I'd try getting hold of the pukka Saab test gauge and try it to see if it agrees. [/qb][/b]
The question is about an auto transmission car, so the level of max boost is alot lower than on a manual car. I'am not aware of that engine, but if we look at a stock 900/9-3 auto trans, we will find that max boost is 0.45 on all of the gears.

Before making any conclusion I advise you to check what stock values for that engine are.
 

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0.5 bar sould like base/lpt boost levels to me, but your car did seem to pull well with 4 FB's in it the other day.

I would have thought you'd be at about 1.0 bar with stg2

The other -ve figures seem ok (considering the overrun and an auto).

Andrew
 

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Hmmm, I thought my car was the fastest thing going for a while even though it was on base boost... (This was when I'd just bought it and in straight comparison to my '90 CD Carly) It felt as though it would rev and rev as the boost doesn't taper like it will when it has it's full complement of psi in the mid-range.

Check that the APC is working Leon, mine wasn't!

Nick.
 

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Vigge... I've driven Leon's car, so I know it's an auto and also how much it pulls, so that's why I know 0.5bar seems too low
 

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I am not by any means saying I have the answer, but it is entirely possible that the nipple you used is at a point in the manifold that shows lower pressure. This could be due to a combination of the flow rate and turbulence in the air stream. If it would not be too difficult, you could tap into a different place and see if it makes any difference.

Also, what does Speedparts list for boost for your car? I would hope they can give you some kind of info on the boost pressure it is supposed to make.
 

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Originally posted by Mark E:
[qb]Vigge... I've driven Leon's car, so I know it's an auto and also how much it pulls, so that's why I know 0.5bar seems too low      [/qb][/b]
Well if it does not pull, then there obiously is a lack of boost.
Like a state earlier, I dont eaven know what stock values for that engine are. The value that stated is taken from WIS.
Ask Speedparts, but be aware that have not made the softaware and therefor might not know what value should read.
 

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Originally posted by Leon [9-5 stg2]:
[qb] I can certainly take it off a different source, worth a go!
I just want some hard facts, before I go for the next step..       [/qb][/b]
Take the boost line from BPV control hose. This will give you Mainfold pressure. I do not know if your car has a solenoid valve. Description

In a de-energized state, a solenoid valve will connect the BPV valve control line to the intake mainfold after the throttle. During deceleration, the vacuum will open the bypass and connect the turbocharger outlet and inlet, preventing cavitation. During acceleration, the solenoid valve will operate and the control line will be connected before the throttle. This ensures that the bypass valve is closed securely under normal driving conditions. The solenoid valve is powered from the main relay and is grounded from control module pin 51.

So if your car has this solenoid valve then you wont get mainfold pressure out of that line all the time due to the description above. But if this valve isnt there the vac line goes dirrectly to TB. Have a look and see if there is a solenoid valve, just follow the vac line from BPV and see where it goes.

You can also make a junktion to FPR control hose.
That line goes to TB also.
 

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Originally posted by Vigge:
[qb] QUOTE
Originally posted by Mark E:
[qb] Vigge... I've driven Leon's car, so I know it's an auto and also how much it pulls, so that's why I know 0.5bar seems too low       [/qb][/b]
Well if it does not pull, then there obiously is a lack of boost.
Like a state earlier, I dont eaven know what stock values for that engine are. The value that stated is taken from WIS.
Ask Speedparts, but be aware that have not made the softaware and therefor might not know what value should read. [/qb][/b][/quote]Vigge, Mark E was saying yes it does pull, very well infact!, better that 0.5 bar's worth.

Andrew
 

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And I've seen Leon's 9-5 on the autobahn and rode in it on the Ring and can confirm its got lots of pulling power!

Does it still pull the same, Leon?
 

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Having never lifted the bonnet on 9-5 LPT (or started life as an LPT) I am curious, do they have the wastegate control solenoid valve? If they don't, then surely your stage 2 upgrade can't significantly alter the boost pressure, just the timing/fuelling.
My 9000 2.3Eco didn't have it so it was just direct mechanical (pneumatic) boost control.

I have to say that at 0.5+ bar boost it was pretty quick, hugely different to 0.3 bar or 0.4 bar. I always thought that if an FPT gave 1.0 bar, that the increase from 0.5 to 1.0 couldn't be as drastic as from 0.3 to 0.5

Maybe the setup on an LPT (higher compression?) doesn't need as much absolute boost pressure to produce the power?
 

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Originally posted by SJ:
[qb]Having never lifted the bonnet on 9-5 LPT (or started life as an LPT) I am curious, do they have the wastegate control solenoid valve? If they don't, then surely your stage 2 upgrade can't significantly alter the boost pressure, just the timing/fuelling.
My 9000 2.3Eco didn't have it so it was just direct mechanical (pneumatic) boost control.

I have to say that at 0.5+ bar boost it was pretty quick, hugely different to 0.3 bar or 0.4 bar. I always thought that if an FPT gave 1.0 bar, that the increase from 0.5 to 1.0 couldn't be as drastic as from 0.3 to 0.5

Maybe the setup on an LPT (higher compression?) doesn't need as much absolute boost pressure to produce the power? [/qb][/b]
To my knowledge all T7 car are equipped with wastegate control solenoid valve. At least this is the case with 9-3. I'am not too familiar with 9-5's, but I could bet this applies to them as well. The older models are fitted with one once upgraded.

Sorry about my earlier comment, I missread Mark E's comment.
 

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Hello Leon,

With the maptun stage 2 max boost at wot was 0.9. I've got a very stable 0.8 bar between 1900-4200RPM. I will have to measure it again, since i've tweaked the wastegate actuator a bit. I made it 1.5 turns shorter. This advice was given to me by Fredrik (Maptun) and makes a nice difference.


It would be nice if we could compare the two upgrades once... It's gonna be a bit difficult tho

Marc
 

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When I got my Hirsch ECU upgrade, the garage also modified the base boost pressure up to .45 by adjusting the wastegate actuator.

I think Leon has Speedparts/BSR ECU on his, wonder why they don't advise the same when fitting ?
 
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