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Discussion Starter · #1 ·
Ok I was just doing some research on the SAAB Automatic tranny fitted to some of the sister cars in the fleet (Viggen and the 9-5) and I came across an interesting tidbit and wondered if anyone has seen this in the 9-3 Automatic as well. The tidbit is related to the torque output from the tranny during wheelspin. On the 9-5 and the Viggen Automatic the tranny (in T7 Form) has a feature built in to reduce the torque output to the wheels to avoid damaging the tranny (in essence like a limited slip diff but not as good). Now I have not seen this in my 2000 9-3 SE Auto as of yet but I also don't see alot of wheelspin either unless I am driving quite agressivley.

Also I was looking to see if anyone made a LSD or a lockup convertor for the 9-3's if anyone knows of a manufacturer out there? I have been unsuccessful in finding one as of yet.
 

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Quaife makes a LSD for Saabs as does a company called Sellholm.

Not to nitpick but Viggens were never available with an auto.

There is a transmission control module that monitors torque and will limit the amount of torque sent to the wheels if there is excessive wheel spin like you mentioned. This is also something that has been thrown out when discussing tuning an automatic car as if the module will limit torque to stock power levels much like the way people say T7 will limit power. I'm not really sure what the real answer is though.
 

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viggens are torque limited in 1st (aronund 190tq) and 2nd (around 270) they finaly get full torque in 3rd
 

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Discussion Starter · #4 ·
xaamottomaax said:
Quaife makes a LSD for Saabs as does a company called Sellholm.

Not to nitpick but Viggens were never available with an auto.

There is a transmission control module that monitors torque and will limit the amount of torque sent to the wheels if there is excessive wheel spin like you mentioned. This is also something that has been thrown out when discussing tuning an automatic car as if the module will limit torque to stock power levels much like the way people say T7 will limit power. I'm not really sure what the real answer is though.
I do apologize it was actually the European Aero model of the 9-3 I saw not the viggen. But what I was reading said it does not limit the motor but rather did the limiting at the tranny level instead. But the article did say the Viggen had a similiar system on it hence the limited first and second gear torque that was mentioned in the previous post.
 

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this limit in torque u r talking about is the electronic throttle closing itself.... i monitored this in 2 ways this passed summer..... while driving in the rain i wanted to see what would happen.

i turned tcs off, and used my boost gauge and tachometer to monitor this.... i was driving in the rain up hilll and made the tires lose traction by flooring it and inducing a downshift... what happened next amazed me as i have never seen anything like it before. i watched the tach down shift (i.e. hit higher revs fast then while the wheels spun the rpm actually flew down real quickly. at first i thought it was just the tires catching grip but it wasnt. i then watched my boost gauge and instead of actually holding boost while tires spun, the level of boost went down almost to nothing and then came back up... this has happened to me on quite a few occasions without me trying to do it again... it seems that it doesnt want to let your tranny get all the torque.... since this i have actually taken out my smbc and will drive around for a month(come spring) and i will see what other funny things my car can do and control, to slow me down
 

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I have had a similar thing happen, when running my stage 1 ECU and once in the cold weather on stock SW...

on full throttle from a low gear/speed, a slow roll....... the engine revs very loud and high RPM then the revving almost "skips" , like my foot is floored but the engine backs it self off for a fraction of a second and then goes right back up to full RPM, while the tires spin. I assumed this to be the torque limiter function stepping in to regain some control over the situation. either that or the gears are slipping and I need to stop beating on my car. :roll: :lol: it happens with and without TCS running.
 

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ricot83 said:
dan this is exactly whta i tried to describe, though u did a better job
sweet. Now i feel better knowing it is not just my car that does this....
:)
That means my gears are not slipping and I can continue the abuse when I put my stage 1 back in the spring. :wink: :lol:
 

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does your car "click" when it does this. granted this only happens on stage 1 SW, but...sometimes If I mash the pedal from a low speed like below 15mph...it will spin the tires like mad and with TCS off it will rev real hard and then hit like a "wall" and go CLICK CLICK CLICK CLICK for a second before the tires regain traction and it shifts up a gear and then takes off..... it sounds almost like it is hitting a rev limit or something and bouncing off the limit back and forth... :? I never was able to notice the tach while it does this as the noise is loud and takes me by surprise and I don't wanna duplicate it if it is harmful. :shock:
 
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