Mods to an auto trans

[XAAMOTTOMAAX]

I just bought a 2000 aero with an automatic trans. I had been planning on some performance mods (not sure which yet...probably one of the stage 2 kits out there) but since noticing the lower torque numbers for the auto vs. the manual, I began to wonder if the auto was capable of handling the additional power or if anyone has any experience with the reliabilty of a tuned auto. Also this is by far the most informative site I have found on tuning the 9-5. KEEP IT UP!
Thanks

[mr saabman]

Hi and welcome to the board :)
I know of someone who is running a STG 2 with auto trans and 246bhp 8) I know his is OK! I'm sure he'll be along soon to tell you all about it :cheesy:

[XAAMOTTOMAAX]

I could expect closer to 280hp with a stage 2 on my Aero. Has anyone driven the auto with that much or more power for an extended period of time? Thanks for the feedback!

[murphwiz]

You can throw loads of power through the trans.. 280bhp should be ok..
The killer is the torque :o
And with a saab engine you get plenty of it, but this will be limited by the TCM, which will tell trionic to lower the torque value to its given setting..

Oh and its mine thats the 246bhp autobox'd 9-5... speedparts stg 2 :cheesy:

[XAAMOTTOMAAX]

I think I have ruled out the ECM. Let me ask you this...if I install some simple bolt on items (performance air filter, cat-back exhaust, maybe Abbott's inlet pipe) would the car still run smoothly or suffer any sort of ill effects? I plan on the car being louder (look forward to it actually) but are there any other things I should keep in mind?

[mr saabman]

Yes the car will still be fine with those mods :)

[Toreador93]

Murph, do you know how much torque you're putting out? On the Speedparts and Genuinesaab sites it says 289 ft lbs for the Stage 2; and a response from Genuinesaab said that the torque was limited in the automatic transmission, but didn't specify.

Would there be any way to mod the auto trans to better handle the torque? I don't know much about transmissions, but would it be possible to replace one (with say, a later saab or even another manufacturer)?

Also, if you've driven a 230 hp and/or 250 hp Aero, how would you compare your acceleration to those (0-60 and 1/4 mile figures are welcomed)? I've been wondering that.

Thanks again

[murphwiz]

The auto trans limits it to 310nm...
I'm looking at other options at present... :wink:

Difficult to compare to the aero's, I've driven both 230/250, but both were manuals, different kind of grunt :lol:
Although the 250bhp aero owner drove mine seemed suitably impressed!

[Toreador93]

310 Nm (229 ft lb)? Isn't that what the V6 puts out? Do the Aeros use different transmissions?

Road and Track clocked the 9-5 V6 at 7.3 sec for 0-60mph, 15.6 1/4 mile; 230hp Aero at 7.0 sec 0-60, 15.3 1/4 mile (both autos). A bit strange, since I'd think the Aero would have a greater advantage of more hp, torque, and weight; but could've been weather related. In any case, I'd guess the Stage 2 9-5 would be right around those figures (if not better).

Please keep us posted on whatever you find about the auto trans!

If a 250 hp owner is impressed, I'm sure I'll be thrilled with the Stage 2; when I can afford it, that is (debating on whether or not I should upgrade suspension to Eibachs first). :)

I've driven the 250 hp auto, and I was very impressed.

[murphwiz]

The 230bhp aeros use the same transmission...
but...
The TCM is different, as are some outdrive gears.... I suspect stronger??
But even the Aero's torque is limited compared to the manual version :roll:

On the Eibach front..
Do waste anytime, get them!
Had the full shock and spring pro kit on mine for a year... superb! great ride, and brillaint handling, and the 35mm drop makes it look just right! :cheesy:

[Toreador93]

What is the TCM? Transmission Computer Module (guessing)? If so, can it be replaced, along with the gears? And how much would that cost?

Is it that the auto Aero has less than 258ft lbs (350 Nm), or the manual Aero has more?

I'm pretty excited about the suspension! People say they feel nausious when they ride with me. :D

How much did your suspension (plus labor) cost, if you don't mind? I haven't been able to find many figures. Did you also install an anti-sway bar? And will my stock 215/55/16's be fine with the lowered suspension. I don't want to rub my fenders off or anything.

Thanks for answering all my questions, I really appreciate it!

[murphwiz]

Your right about the TCM..
no idea on what the differences are between aero and normal TCM yet... still working on it.,.. :wink:

The full Eibach kit cost me £500 Ukp..
although it can now be had cheaper, and I fitted it myself in a hour or two.
Plus the rear camber will probably need adjusting afterwards due to the change because of lowering!

I'm running on 225/45ZR17's and never had a touch... it lower by 35mm from standard but its not that low, just looks 'right' :cheesy:
http://www.btinternet.com/~leon.murphy/misc/9-5side.jpg

[2Griffins]

Hey guys, I've got a 2002 Aero (250hp) which was the first year for the new 5spd auto in the US. I wonder if this is a stronger trans because, if I'm not mistaken, the auto in 2002 got just as much torque and hp as the manual and even took advantage of the overboost feature on these cars. Perhaps this could be a good swap trans for those with earlier cars who want more ponies. Does anyone know the torque rating for the 2002 and up 5spd auto and is it different from the 5spd auto Selectronic?

[murphwiz]

The torque for 02 aero autos is same as manual 350nm, but still no overboost on the autos, this is a manual only function.

[2Griffins]

The torque for 02 aero autos is same as manual 350nm, but still no overboost on the autos, this is a manual only function.

OK, I thought it got overboost too....I could swear that in "Sport" mode the boost needle will venture into the red zone just a bit. It certainly has a lot more energy in "Sport" mode but I guess that's just the electronic throttle being a tad more aggressive.

[murphwiz]

The boost gauge is programmed, it bears no resemblance and has no physical link to the boost!
In sport mode the effective throttle travel is reduced, so the engine feels a lot more lively for the same amount of throttle travel, but power and torque are still the same.

[Toreador93]

Would it be possible to swap the transmission to a newer one (either 4sp or 5sp)?? Though it'd probably be expensive...maybe from a salvaged car?


On the suspension topic, did you replace any of your bushings?

[murphwiz]

Should be possible to change for any other 9-5 4 speed auto yes..
I've been investingating converting to manual also... but seems a lot more trouble than its currently worth!
I very much doubt you could just put the 5 speed auto in without some other changes, possibly require new part of loom etc...

On the suspension, no all i've changed are shocks and springs, if bushes need replacing I'll be keeping to standard rubber, as mines a daily driver, the poly's transmit too much road to the car for everyday use in my opinion.

[Toreador93]

Out of curiousity (as most of my questions are), how much time and money would a manual conversion cost? What would be involved?

[murphwiz]

Well I'd estimate up to 2 days labour...
Plus the cost of all the parts, box, pedal assmebly, pipework, clutch slave and master cylinders, gearlinkages...... the list is endless, if I was to attempt it, I'd get a wrecked 9-5, pref a rear ended one, and swap side to side.