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Discussion Starter #1
A friend of mine said that a Saab tech in Europe told him you could swap the opposing hoses on the APC (87t) for increased boost but you needed to keep an eye on the guage. Is that too risky to try?
 

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If you really want to raise boost easy, just buy a manual boost controller. You have to watch out for knocking and leaning out. Maybe some early 9000 or classic 900 guys can chime in and help out?
 

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if you dont mind soldering some resistors, replacing a pot with wires to lead out to the dash and putting a new pot on it, you can mod the APC itself and have a manual boost controller on your dash.. and you dont have to worry about detonation, coz the APC still controlls the boost according to the knock sensor. Do a search for APC mods and you may find how to do this. I just want a 2nd hand APC unit first to try it on, then i will have a spare stock computer
 

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Cockpit adjustable boost would be nice and I am assuming that you replace the screwdriver adjustable boost control slug in the APC unit with a potentometer on the dash but I would really like to know more about this and if there is a "howto" written somewhere for doing it. If you have more information; please share it!
Thanks
 

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Discussion Starter #6
Thanks for the input all but I don't see how any of that is easier than swapping APC hoses.
I guess I'm looking for someone to talk me out of it.
 

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Originally posted by chucktv:
[qb]A friend of mine said that a Saab tech in Europe told him you could swap the opposing hoses on the APC (87t) for increased boost but you needed to keep an eye on the guage. Is that too risky to try? [/qb][/b]
I'll do it. You think you will always have your eye on the gauge tp make sure you are not overboosting? Also, what is telling you that your engine is not detonating/knocking? Thats right, nothing. For pure engine safety reasons, you want the APC to have complete control over the boost and swapping the hoses probably screws with the control somehow. You already mentioned it by saying it would raise the boost.

Is this what you were looking for?
 

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Discussion Starter #8
That's more like it. I've just gotten my car running the best it has since I've had it and I'm not going to do anything stupid (at least not too stupid). I was hoping someone had heard of this before and could explain what effect it has, good and bad.
 

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Discussion Starter #9
One more thing, Eric, I believe my 87's APC only controls the turbo and not ignition timing since it's not DI.
 

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Wow!! This is sooooo going over my head.
Can anyone pin a glossery or acronims on the board so I can understand everything.

And I thought geing a biker was bad
 

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APC: Automatic Pressure Control - came in on the '80s 900 Turbo. Uses a knock sensor to control boost pressure, and backs the boost off if it detects any detonation. Allows the car to run on any grade of fuel without fear of detonation or 'pinking'.

DI: Direct Injection. Saab's ignition system, takes the form of a cartridge which sits in the recess on top of the cylinder head, and has a separate coil for each spark plug. So no need for a distributor, and ignition timing becomes infinitely variable.

You'll hear of 'DI/APC' cars, which are from the early '90s (I think) and had both of the above. At some point ('93? '94?) both funtions were incorporated into Trionic, Saab's all-singing, all-dancing engine management system.

One more abbreviation: T. Turbo.


Cheers

James
 

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James, if I were a pedant I would say that APC means "Automatic Performance Control"

1980 The APC system protects the engine from injurious knocking due to uneven fuel quality and enables the engine to be run on petrol of various octane ratings. The APC system goes in production on the 1982 Saab 900 Turbo.

(looks like I'll have to buy you a beer, then!)

T normally denotes Turbo equipped vehicle putting out around 175-185bhp
t normally denotes "Light pressure turbo" or LPT putting out around 145bhp
HOT denotes High Output Turbo, used on engines putting out 200bhp or more.
...no doubt with some exceptions and intricacies.
 

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T normally denotes Turbo equipped vehicle putting out around 175-185bhp
t normally denotes "Light pressure turbo" or LPT putting out around 145bhp
HOT denotes High Output Turbo, used on engines putting out 200bhp or more.
...no doubt with some exceptions and intricacies.    

 [/b]
Indeed true.. if the engine is a 2.0... if it's a 2.3 Litre engine.. then the numbers are higher.
T - circa 200hp
t - circa 150 to 180hp (depending on if it's a 9000 or a 9-5)
Aero - 225hp unless it's an auto.. in which case - 200hp.
Viggen - 225-230hp.
 

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Originally posted by James:
[qb]Out-anoraked again    :rolleyes:        

Incidentally whilst looking for pages containing 'APC' I found a useful page on Saabnet    :eek:  

List of acronyms

Now I know what DICE means    [/qb][/b]
It says: LPG = Liquid Petroleum Gas but LPG actually means Liquified Petroleum Gas. I think we have gone a bit off-topic. I think I shall go for a walk in the park, now.
 

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Out-anoraked again        

Incidentally whilst looking for pages containing 'APC' I found a useful page on Saabnet    

List of acronyms

Now I know what DICE means    

 [/b]
Ha.. they've missed out - EGT (Exhaust Gas Temperature) - My least favourite acronym.. and WOT (Wide open throttle) - my most favourite acronym.
 

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Discussion Starter #19
Originally posted by /john:
[qb]I think we have gone a bit off-topic.  I think I shall go for a walk in the park, now. [/qb][/b]
Actually I think the topic has been oblitertated since there where far more replies to the anachronym question than the original.
However I did learn that I've been using the incorrect t. I should have been using 87T. Too lazy to hit the shift key, I guess. That being said, I'll still gladly accept further opinions on the initial question
 

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I have a 9000 auto and I have worked out a very easy way to get controlled extra boost.First hook up a gauge that is calculated and see what you get now and compare to your dash gauge then on the APC valve cut the middle rubber hose near the valve and put in a "T" piece and on the open side of the t piece fit a short piece of hose and close it off partially with a blank with a 1mm hole in it, this will bleed off some of the boost pressure going to the wastegate thus raising your boost, experiment with the blank hole size so that you end up with no more than 14psi hot. This has worked very well on my car and no adverse effects during the last 3 months and it has given me a very usefull power boost when needed. But remember make sure that all is well under the bonnet before subjecting the engine to the extra power. my engine has the individual coil packs and a full width intercooler and I run on premium unleaded and use Penrite 40
 
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