[California Saab Tuner]

Abbott racing e-mailed me saying that you could not use water injection on a T7 engine management system. I still haven't heard any difinitive evidence as to whether this is true or not. Is the new boost pressure AND temp sensor hiding a water detection sensor of some sort? Was abbottracing just having trouble with other aspects of it?? Or was their kit just not really designed for the T7 cars and they wanted an excuse? lol Any help would be much appreciated!

 

[grentarc]

They didnt give a reason on why it wont work on T7's? i would be asking for the reason why it doesnt work....

 

[1989agoodvintage]

It's probably because the T7 is "too adaptive", for similar reasons Dawe's devices cannot be used on T7 cars, the Trionic system detect's an unexpected change and compensates. As far as I understand it anyway ...

 

[California Saab Tuner]

But they said it just "shuts down" and they wouldn't explain why. :S Like it detects water in the system and shuts the engine off as though the intake had been submerged. And actually, while you can't use dawes devices on the T7, you can up the boost with an MBC ... it just doesn't like it, and won't give you any horses really. It retards the timing, or closes the throttle or something (damn the electronic throttle). But the water injection must be setting off some sensor. The local Saab master tech couldn't even understand why it would do that. Or tell me what sort of sensor could detect that. He said the most likely cuplrit was the homologation of the Boost pressure and charge temp sensors into one sensor. That perhaps they included a water detection sensor. But he wasn't sure, and I'm curious if anyone has solved this problem.

 

[brent]

I say if it wont work....it wont work.....

just get a bigger I/C....

that should cool things down......


I got a T7 too just have to work around its dum flaws.....

 

[sj]

Just a guess, based on how 'too smart for its own good' the trionic seeems to be...

Perhaps water injection will give the sensors a boost pressure reading which is deemed 'impossible' at that temperature reading (or vice versa). The wonder electronics then assume that one of the sensors is faulty and switch to a safe mode??

 

[Eric van Spelde]

This thread may be of interest to you:

http://www.saabnet.com/tsn/bb/performance/....html?bID=65219

Apparently, there are advantages to running water injection on T7 in that the car will hold the max boost that Trionic will allow over a wider range of conditions.

 

[California Saab Tuner]

lol That's what I was going for. Especially after a few upgrades. Actually I've read a dissertation or two now on water injection. The reason it actually "decreases" performance on stock computers at low boost is because it moves the Peak Pressure Point to a later Crank Angle. However, the cooler and denser air makes the ECU think it's under more load which causes it to retard the timing (it needs to advance due to the slower burn) and move the PPP even FURTHER back. If you have an ECU designed for water injection in can increase power and even gas mileage at "all" conditions, however I do not know of any tuning company specifically desinging spark controll systems taking water injection into account because the computer would need to know if the water injection was on or off. However a large advantage can still be had from water injection a stock, or modified turbo car. This advantage is the knock threshold. Water injection SIGNIFICANTLY increases the knock threshold. Allowing far more boost on lower than ideal grades of gas, and in warmer than ideal temps. This significant reduction in knock sensitivity at any temperature is something that no intercooler can boast, and the reduction in temp as a result of the water being injected is only a secondary benefit.

Since it is clear someone has already water injected a T7 Viggen, that will be on the slate for future upgrades on my Viggen. First off being catless downpipe (it's only illegal if you get caught! ) a better intake pipe, MapTun computer, and bigger intercooler.

Oh and I should note, one of of the previous links, there was a 99 Viggen with 77K miles, water injection, intake filter, and downpipe putting 248hp to the wheels. Since that car is rated 5 hp lower than mine (likely with good reason), perhaps in cool weather mine really does have "close" to 252 hp like I was lead to believe by the g-tech. We'll see. It feels much more consistent with these new plugs. I think this engine has far more power than people are led to believe by it's "rated" figures. I can't wait till it's cool enough to dyno it. Needs new tires and brakes before that. Damn TWR rotors that lip after 25K miles. Getting Group9Performance Brembo's if they fit the Viggen. Says "all" 9-3 models. So they'd better make a 12" one for the Viggen!!

Yours Truly,
Adrian