Saabscene Saab Forum - Saab Technical Information Resource banner
1 - 6 of 6 Posts

·
Registered
Joined
·
2,277 Posts
Steve,
This is about right for an otherwise standard car.
To give yourself a chance to see what more boost feels like (and to recalibrate the engine management) remove fuse 5 for a few minutes and then replace. Go for a drive and you should see the boost go into the red by a bit (at full throttle of course) until the management recalibrates itself (this will happen after just a few full throttle applications through 2500-3500rpm).
This might give you some more boost long term IF the management had lowered its' limits previously due to dodgy fuel or some other temporary malady.
Enjoy it in the mean time.
Nick.
 

·
Registered
Joined
·
8,216 Posts
Originally posted by steveb:
[qb]At present the needle goes halfway across dashed orange sector[/qb][/b]
I agree with Nick. This is about right for a 2.3T auto (the auto Aero engine was the same as any other 2.3T auto). This is less boost than the manuals because boost (and hence torque) is limited to avoid damaging the auto transmission. I believe it should be around 0.8 bar maximum, which will probably reach just about where your gauge is reaching.
 

·
Registered
Joined
·
1,908 Posts
Anyone know why the 9000 autoboxes are less robust than the manuals, in terms of ability to handle 225BHP?

Whilst the USA is largely an AUto-box market, many of the big engines out there pump out well in excess of 225BHP with an autobox.

I am also told, rightly or wrongly, that some US car manufacturers do not produce high power variants with manual boxes because they are not as robust as the USA Autoboxes!!?! Strange.

Any USA BB members able to comment on this latter point?
 

·
Registered
Joined
·
8,216 Posts
It is not the power output that is the problem, but the gobs of torque produced by the turbocharged engines. The 200hp auto and 200hp manual are not equivalent either, with the auto producing just slightly under 300Nm of torque compared to around 320 (or 340?)Nm for the manual. I believe this particular auto transmission is rated up to 300Nm, so Saab went near the specified limit. This should have been OK, though, if ZF got their sums right. Perhaps the figure was a bit marginal.

There are auto gearboxes that can handle a more torque, but I'd be willing to bet they would be hard to fit in the available space on the 9000. The 9000 design had been in production for about five years before the 2.3T variants came along, so I imagine someone had to decide what type of gearbox would fit and found they couldn't fit anything more heavy-duty than what was already in use (and ZF said that unit would do the job anyway).

The problem with putting high power/torque through manual boxes is both that you need a lot of clutch and that it is easy to abuse the transmission if you don't get gearchanges right. An auto can control things more precisely and gently.
 
1 - 6 of 6 Posts
Top