15-12-02, 02:23 AM
I have a '90 2.0 Turbo Cd. I have read that the 2.3 head flows much better than the 2.0. I also already know that the intake off of a 2.1 or 2.3 is needed. My question concerns the exhaust manifolds. Are they the same between the 2.0 and 2.3? Also, I have the T25, does this use the same mounting flange as the T3 and larger? I was told that a new flange is needed for a larger turbo.
Regrading cams, do the 2.3s have larger cams and is thus an upgrade just merely bolting on complete 2.3 head? What are the differences in the 2.3 heads/cams for N/A and turbo?
Thanks in advance,
15-12-02, 10:13 AM
I'm not at all an expert on the differences between 2.0 and 2.3 liters engines, but I will try and answer the questions I can...
From what I know the 2.1 intake only fits the classic 900, but the 2.3 liter will fit together with the 2.3 head on the 2.0 engine. Be sure to get a 2.3 head from a car up to -93 since they changed the design a bit from -94 ("long" engine up to -93 and "short" engine from -94)
I dont think that the T25 and T3 uses the same flange. But if you have a T25 and want a bigger turbo you can get your T25 mashined to take bigger turbine, impeller and ball bearings making it a T28BB. I'm going to do that with by own T25. Speedparts in Sweden says that it can cope with 2 bar boost and deliver up to 330 BHP on the 2.3 engine :D
Regarding cams I've heard that the -86 to -88 2.0 turbo cams are the most aggressive stock once Saab have made and I think that they will fit any head - but I'm not 100 % sure. If you want more agressive cams there are cams available in Sweden, both new once and re-grinded...
Hope that this is helpful.
15-12-02, 03:00 PM
Thanks for the insight. I kinda figured that the larger engine would get bigger cams, guess not.
As for the turbo info. I would think it is actually cheaper to get a new turbo than to have the T25 worked over. I am not sure how much it would be to have the T25 worked over, but I have seen much larger turbos (T3/T4 hybrid) for sale for less than 500 USD in new or like new condition. These are not water-cooled, but water-cooling kits are available for most turbos for under 100 USD. Even still, I could pull a T3 off of an older Saab for pretty cheap (~200 USD, good condition) as well.
16-12-02, 12:01 AM
Well, back on topic...
What difference is there between N/A and Turbo 2.3 heads? I am talking complete here. Does N/A have diffent cams and would they be suitable for turbocharging?