Which turbo?

[Julian]

Evening all.

On my list of "Things to do to my 9-3 if I ever find a big pile of money" is a new turbo, since the T25 does tend to run out of puff a bit.

Popular options seem to be the TD04 or a T28/25 hybrid. Can any enlightened soul advise what I would expect in terms of lag, boost and general driveability from either of these?

Ta very much like.

[maartenvandorst]

Last weekend I have visited a Belgian tuning show. I've spend some hours talking to Magnus Uhr from the Swedish tuning firm Nordic. It was the first person that was able to answer all my questions about Saab tuning. We've discussed different turbo's as well.

He's using a T28 in his 9-3 at the moment, but he said the Mitsu TD04's spool up is better.

The T28 is a direct fit (only the internals are different from the T25), for the TD04 the oil and coolant lines have to be changed, I think.

[billj]

Owning a 9000 2.0LPT with a T25 and a (pretty quick) tuned 9000 Aero with a TD04, I'd say the LPT definitely responds quicker and is probably atually quicker off the line, but the Aero is scary fast and the lag isn't something I really notice until I drive the LPT again.

[john]

Cartwright's only thinking of this after my Sport saw him off last weekend

...but I notice he has neglected to mention that

[Julian]

Make the most of it Winter, it won't last

Thanks chaps for the comments.

[mark e]

I had a 360 degree hybrid GT30, which was very nice. Comparatively low lag, and bags of welly up top. Price around £500 (plus fitting).

Now I've got the mutha of all T3/T28 hybrids which does suffer a little from lag (I suspect this is in part due to the Maptun mapping, and have to investigate further) but oh my word does it deliver up top

[Julian]

Am I right in thinking that a T28/25, retaining the T25 turbine, would give me similar spool up to a standard T25, but the bigger T28 compressor would provide much more in the way of ?

What I am after is a bit more low down response and an ability to maintain grunt factor up to the top of the rev range. I suppose having my pie and eating it is at odds with the mechanics of a turbo though?

The Viggen IC greatly improved throttle response and I expect another positive effect when I fit a straight through exhaust at the end of the month. However, I don't want massive up top power at the expense of increased lag since it is not very often I get chance to use all the power available.

[burre]

I will be going the T25/28 route when I eventually upgrade my turbo. I too, want a better top end but I also don't want any increase in lag. A T28 compressor, being bigger, will cause a bit of lag but it is probably not noticeable. If you want bolt-in, only a modded stock turbo will do, Saab's turbine exits are smaller than those of typical generic T28s.

Have fun!

[StanleyB]

It migght seem a bit off-topic here, but I keep reading the same comment in various conversations, which has ended up puzzling me. They are:
1. Does every 9-3 turbo come with an intercooler?
2. In which 9-3's were the T25 fitted? Mine has a TD04, but I have also seen a TD03 in the car of a friend.
3. What is so different about the Viggen intercooler, compared to the intercooler fitted to a "standard" 9-3?

I hope I did not stray too far off the path with my questions .

[wrighar]

In which 9-3's were the T25 fitted? Mine has a TD04,[/b]

Your also running a Viggen in disguise so a TD04 would be correct TD04 came on B234R and B235R engines (9000 Aero / 9-3 Viggen / 9-5 Aero).

Andrew

[Eric van Spelde]

1) Yes, but there are 2 different types - one which has the inlet and outlet at the same type, and one off 'crossflow' design (one side in, opposite side out) in the Viggen/TID/2000 and later other 9-3 models (?)

2) I think every turbo 9-3 except the Viggen and the Aero has a T25 (although they might have gone to the GT17 at some point for the LPT to align with the corresponding 9-5's) - the Aero has a TD04HL15 with 5 cm2 trubine housing, the Viggen has the same as has the 9-5 Aero - 9000 Aero's have a TD04HL15T with 6 cm2 turbine housing.

3) see 1). The crossflow design is far less restrictive in terms of flow than the older ones.

[StanleyB]

Thanks for those answers Eric. That at least clears up some more looose ends in my SAAB knowledge .

[burre]

As for the intercooler, the GM900s and base 9-3s through the 1999 model year got the intercooler with the inlet and outlet on the same side. The HOT 9-3s got the crossflow intercooler starting in 1998 or 1999. I believe that starting sometime in MY 2000, all 9-3s got the crossflow.

As for the turbos, I think Eric is correct. I think the GT17s started in MY2001 LPTs, but I am not entirely sure.