im pretty sure the stock blocks can handle more than 300hp. And where did u find an ECU for 600...i was thinkin more along the lines of $850 - $1000. ECU and Downpipe are the major mods before upgrading the turbo.....and upgrading the turbo will not be easy. Speedparts uses a garret turbo which will cost u a good bit alone, not to mention you would want to upgrade the fuel system as well. ECU is about 800 min., then a downpipe is about 450 w/o a high flow cat which u need so add another ~150 for a cat plus install. so ur already up to your $1500 limit....these mods will increase your whole rpm range and i dont know if u will want a turbo upgrade that bad after you have these. With these you can probably dyno at 250+ to the wheels. Torque will be monsterous....probably around 300 wheel tq. if not more. A turbo upgrade would detract from your torque.....although that could be good for traction reasons.....but then u would need to support the turbo with new fuel injectors......possibly a fuel pressure regulator. Any a few other things im not thinking of.
I think one of the best upgrades for a viggen would be a cam and an extended redline. It seems as though the viggen makes too much torque for its own good.....and a cam would raise the power band up and reduce some low end torque. I could be totally wrong but it just seems that cams do wonders for V8's and i dont see why it couldnt do good for a Viggen. My buddy has a Trans Am WS6 and he put a full exhaust w/ long tube headers, no cats....most of the intake is upgraded minus the throttle body and somethin else....but just with a cam and these mods he put down 399.99 RWHP and ~380 - 390 tq. This is up from probably 350 whp with the mods w/o the cam
2000 Saab 9-3 Viggen Sedan
-BSR Cat-Back and Intake