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Discussion Starter · #1 ·
fitted a bleed valve over the weekend as the apc valve wos causing very eratic boost, WOW wot a differance, its like having a new car, set it to boost just into the red slashes on the boost gauge and the result is like riding a misile (i imagine). WOULD RECOMMEND IT TO ANYONE. try it only cost £15, but make sure u have clean underwear on!!!!!!!!!!
 

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Discussion Starter · #3 ·
you the man quarryeff.
P.S im new to the saab, got my 9000cs 2.3 turbo 2 weeks ago and wot a car it is, wont be buying anything else but saab from now on!!!!. i wos converted after a dfive of my work mates 1990 carlson, he picked it up with 45000 miles on the clock with full saab history (git). keep up the good postings on this site its great just to flick through them and read your comments on this great mark
 

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What was the name of the thread that had the detailed info obleed valves?
Is there a way to clean the wastegate without undoing nasty, orange ,seized, rusty bolts?
This is me following a different thread , sorry.
 

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I would advise not to touch the wastegate arm unless you know it has been adjusted away from 'standard'.
Your car is normal if the turbo gauge rises into the 'red' briefly before falling back and holding near top of 'orange'. If it doesn't do this then you could adjust wastegate. All you are doing when you shorten or lengthen the wastegate arm is to advance or delay the point at which the gate opens to let out air. That is, it stops the turbo from grabbing too much air.
Afraid the only tip I know about rusty bolts is to invest in some spanners / sockets which are either
6-sided (more awkward to use, but don't take corners off nuts)
or, even better,
spanners / sockets which grip by holding the flats. They will get you out of the 'nut is rounded off' problem. Because they are quite expensive, I only purchased individual ones that are the most common sizes.
 

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You people must think I'm a bore regarding bleed valves as a way of easily increasing a turbo engine's output.
But the question keeps coming up!
ANYONE can fit a bleed valve into a turbo car if they want to. It will cost £15 and take an hour to fit and adjust. A bleed valve is no more than an adjustable hole.
The turbo will take in more and more air as the revs rise unless something puts a hold on the increase. This is what the wastegate does - at a preset point (where the pressure has increased to the point which the manufacturers set) then the wastegate opens and prevents any extra air above this level from entering.
By taking out some air from the control signal pipe ('bleeding') then the opening of the wastegate is delayed, allowing more pressure to build up. Hence more power. The increase in power can be dramatic.
Saabs have an inbuilt system which prevents you going too far. So if you try to bleed too much air, you will notice the engine will momentarily cut when the boost gets well into the 'red' zone on the gauge.
The adjustment trick is to get the bleed valve set by trial and error so that under the highest engine load ( say 4th gear at 50mph on full throttle uphill) the cut point is just avoided.
See other posts regarding how to fit bleed valve into the pipework. The pipe in question is just about the most accessible thing under the bonnet!
 

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Discussion Starter · #11 ·
kswoden,
locate the apc valve it will have three pipes going to it, find which one is marked W (for wastegate) then cut the pipe and insert the bleed valve, carfull when adjusting the valve as mine is only open a couple of millimetres!!!!. hope my rambling on has simplified it for u, got my valve from halfords.
BLOWER.
 

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You will see bleed valves are small (thumb size) with three openings. The two opposite openings are connected into the two cut ends of the 'W' black poly pipe and the third opening on the valve is just left in free air. With the valve shut you have just the same situation as before you put the valve in.
Check the boost level on the gauge on a handy hill at say 50mph in fourth (accelerate watching needle). It should settle after an initial surge to about the top of the orange.
Open bleed valve no more than 1/4 turn and repeat test run under same conditions.
Repeat, increasing bleed by 1/4 turn at a time. You should note the needle settles higher and higher up the gauge.
If all is going well you will notice the performance drastically increases.
When you have gone too far you will find the Saab control system says 'no more, chum' and cuts the power. In my car this is with the needle about 50% into the red, but I don't think that's true for all cars.
Back off the bleed to what you are comfortable with.
From time to time (air temperature, fuel quality, road conditions, gear you are in) you might get a cut, close bleed a bit if it's a problem.
You can always take out bleed and remake the pipe.
 

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Why not remove the end of the pipe from the solenoid valve and use a "fresh" short connecting piece between the bleed and solenoid?

For £15 it's worth a go, not as a permanent solution but for track days. I couldn't afford the increased insurance premiums that go with making custom modifications.
 

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The better option, I agree 1989... It's just that small bits of pipe never seem to be at hand when you want them. Your suggestion of course means that you can go back to exactly standard with no evidence that anything has been changed. I just mounted mine as close to the solenoid as I could so I could still get the original back on albneit missing an inch or so. Saab were very mean about this length of pipe; it would have been nice to have an extra 2" or so.
 

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I was contemplating fitting a manual boost control (bleed) valve as I would like greater performance. I almost got one but before I did I thought I would get some more expert opinion so I phoned Trent Saab. They are strongly against and say I will lose all the engine protection systems with the trionic car. They also say tricking the wastegate in this way is also a big risk to the gearbox which is fairly close to its limit with a 225 bhp engine. I think I'll just put optimax in it and leave it at that. Any views on Trent i.e. might they be saying that because they don't sell the valve- but odd to talk about the gearbox limitations when they are also in the market of engine upgrades?

Julian
 

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I use Trent Saab and I'm very happy with them, that said they ARE in the business of selling "proper" performance parts. They'd rather you asked them to fit a motorsport wastegate to improve boost rather than for you a DIY work-around. That said I don't think they are in the business of exploiting people. Quite rightly they probably don't want to be in the business of fixing cars damaged by DIY mod's, it wouldn't do their rep much good.

Come back to this page in 6 months and we can get a true idea of what risks the bleed valve really incurs. I think there may be a few horror stories to counter-balance the favourable ones.
 
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