Tuning you GM900 [Archive] - SaabCentral Forums

: Tuning you GM900

13th September 2002, 06:31 PM
I'm new to the board and would like to help out anyone interested in tuning their GM900 Saab. I have a lot of info on my website, check it out.



Mark P
14th September 2002, 02:26 AM
Super site Eric!

A must for anyone wanting to mod a GM900. Have a look! :D

Mark P

14th September 2002, 02:52 AM
Excellent stuff Eric!

14th September 2002, 03:18 AM
Excellent site. Really useful.

However, can I just check that you still have the MBC set up as you indicate even with the stage 3 ECU? It would seem to me that the MBC used in the way you suggest would defeat some of the job the upgraded ECU does.


14th September 2002, 03:58 AM
this is great info and links, thanks. also, do the viggen exhausts and the 9-3 exhausts fir a 1995 900s? im looking for the best possible exhaust to put on my car that is not very loud.

14th September 2002, 11:49 PM
Alanb - I still have my MBC controling boost, however the reason is because my boost solinoid is not functioning correctly. I haven't used it for a year, and when I hooked it back up after the new ECU I was only getting 10 psi max. Even if the solenoid was functioning though I would still use the MBC. I like have full boost in 2nd gear.

chuckles07@aol,com - Both the Viggen and 9-3 sport exhaust will fit onto a GM900. However I am unsure of the exhaust volume of a 900S. Turbos also act as mufflers, I even ran atraight pipes for a while and it was tolerable. I suggest posting the question on Saab Net on the NG900 board. I bet that there are a few 900S with sport exhausts. http://saabnet.com/tsn/bb/NG900/


18th September 2002, 11:48 AM
Nice, site, and some good tips (looks like anyway).
I hope to be able to put some right to the test, I'm sending off the check today for a 1999 9-3 that I'm buying in PA, and then I'm having it shipped out to NW WA.

18th September 2002, 01:29 PM
hey, I have a 97 900 SE and was thinking of getting a new ECU from Engstrom.net. I was just wondering how effective the upgrade was and if you have had any problems with it?

21st September 2002, 04:40 PM
dschneid25 - I love my ECU, it's great. But I would suggest that you do other things to your Saab first before you get an ECU. Intake, sport exhaust, MBC and Viggen Intercooler will put you at good power level. Plus they cost about the same as an ECU anyways. Then if you stil want more power you can get a stage 3 ECU.




21st September 2002, 10:10 PM
What do you think is the best way to start out adding some power to a N/A 97 Saab???

23rd September 2002, 08:30 AM
what are some cheap and affective ways for me to upgrade my 900s v6 (non-turbo) for bhp gains. I am having trouble finding parts.

24th September 2002, 01:33 AM
I'm sorry slob900 and jvm123 but I do not have any good information for you in regards to tuning a NA Saab. But there is hope out there, check out this picture I took of the engine bay of a 2.3L GM900 at the Saab Owners Convention this year.


some more pics at http://saabpics.nailed.org/gallery/900S

Apparently his NA Saab is putting out ~277 hp, so it can be done. Keep an eye on Dave, he recently purchased an ECU upgrade for his 2.3L GM900, he should be getting it soon. Here is his original post. http://saabnet.com/tsn/bb/NG900/index.html?bID=74891

Good Luck


24th September 2002, 01:35 AM
is there any listed email address for this guy with the beast NA. i really want to ask him questions!

24th September 2002, 01:42 AM
He goes by the nickname Meatball, but his posting name is 900S. Follow this link to see is posts on another board http://saabnet.com/tsn/bb/NG900/index.html?by=Author&a=900S


14th October 2002, 09:24 AM

Sell it and buy a turbo car..

You can literally spend thousands of dollars getting 5 to 15hp extra (Sports exhaust, low resistance intake, port polishing, ECU) and never really notice the difference.

Or with a turbo car (especially a trionic5 car, changing the ECU programming, a manual boost valve, good sports exhaust, removal of heat plates, a bigger down pipe, cross-flow intercooler, polished throttle transition castings etc, you can easily take a 185hp car upto 230 to 240hp - and this without removing the CAT etc..and a heck of alot cheaper than adding 15hp to a NA car..

Check out STTE.. there are a few owners of 9-3 and NG900 cars that have done the above.. have a chat with them!


Eric van Spelde
14th October 2002, 10:06 AM
OK, time for me to share this wild and unconfirmed rumour.

Let's start off by establishing that there is a Dutch Opel Calibra 2.5 V6 owner that had his 2.5 short block replaced by an Omega 3.0 V6 lump, together with his existing 2.5 heads (note: the complete Omega MV6 engine will -not- fit under a Calibra's bonnet, but apparently the block together with the 2.5 heads is a straight fit). This car has been featured in a Dutch car mag as well as in at least one German Opel fanzine.

Now earlier this year, at the Speed 2002 show, some guy came to us and claimed he had one of 5 pre-production Saab 900 V6 examples with 3.0 rather than 2.5 litres of swept volume! He said he bought this car, had it serviced by a Saab dealer and they told him that from the engine # they saw it was a 3.0 litre - the story was they built five of them for the press introduction of the GM900 so that the journo's would say "wow, this thing goes pretty well for a 2.5 litre...' A wild story indeed, but then it was either Car of Top Gear that rather liked the V6 back then and said the Turbo was 'a bit of a letdown' in comparison - all of us know, as later sources rightly report that the Turbo was faster and as least as smooth as the Opel V6. So maybe the Trolls -did- pull a trick at the press intro...

Anyways, if I had a 2.5 V6 I would be researching to what extent the Opel and Saab 2.5 V6es are identical with regards to engine mounts, block casting, ancillary equipment postions on the block, etc. If the basic blocks are indeed the same (i.e. all mounting plates, etc. can be swapped from one engine to another) there is no reason why the Opel/Vauxhall 3.0 bottom end could not be swapped into your 900's engine bay without anyone noticing... :cheesy: