Super Darius:
Buddy,i prefer to be sure on your answer becouse i LOVE that hissing noise
,and sure is due to the increased boost.
So i think that the time to make that Ecu mod on my car is near 
Darius, do what you are comfortable with but "conventional wisdom" -- and I absolutely agree with it -- is that you need to firm up the Turbo's suspension before the ECU tune. The stock Turbo frankly is just way too soft and I am afraid a tuned Turbo will squat and lean like a drunkard walking down the slopes of Positano. It's probably not a good idea to just jack up the power without stiffening the car.
Just a brief summary of my experience with a stage 2 tune (no tuner bashing please -- not the goal of this thread, just reporting my experience):
Pluses:
1. No doubt about this: The gain of power and torque is extraordinary and easily noticeable. I was skeptical of what an ECU mod stage 2 could do, not anymore. On WOT on third, the front of my Bilstein car lifts up as if it wants to go airborne 
. In corners, there is this eerie feeling that the rear will readily break loose with throttle application. Perhaps once I get used to the power gain this feeling will be gone. Perhaps not.
2. Spool up (what happens when you press on gas pedal at 2000 rpm in 5th, in stock car power does not come on until 3000) is less.
3. Lag (what happens when you press on gas pedal at 3500 rpm; here there is no spool up delay, but still a lag): much, much diminished. The car feels extremely sporty and responsive. "Jabbing" on the gas pedal on 5th gear at 3000 seems to feel the same as as 5th gear at 4000 rpm before the mod.
The effect is that the car feels less ponderous. The enhanced agility makes it feel like a fog has been lifted from the car's behavior. It feels very quick.
Minuses (This is just me, most of these no one seems to talk about, so please take with a table size grain of salt, maybe it's my idiosyncracies, or maybe my lack of experience, etc.):
1. The enhanced power is perhaps a bit less linear than stock & could make the car more tricky in corners. Tuned ECU gains power by gaining boost, so I could be wrong but it seems to me most of the gain of any tune occurs after 2900-3100 or so in our turbo. What that means is there is an explosion of power at the 3000 mark, more fun yet also a bit more tricky.
2. "Engine braking." What I mean is this, at say 60 mph, there is a difference between driving a car at 5000 rpm and driving one at 3000 rpm. At 5000, when you let go of the pedal, the car jerks as if it's more connected to the engine, at 3000 it doesn't. The tuned car does this more and therefore feels less relaxed on cruising. If you are tired from work and just want relaxed crusing, my opinion is the stock car is better.
3. Change in exhaust sound and noise. This problem is perhaps particular to my car, or my sensitive golden ears 
, since no one but me seems to be talking about it. Basically after the ECU mod, there was a significant change to the sound of my beloved Cargraphic exhaust. The low frequency rumbling/growl that I so love is gone, the overall sound becomes higher pitched and more high strung, and in cabin noise is quite a bit higher. After my initial complaint, it was noted that the EVOMS tune increases idle rpm from 750 to 840. EVOMS was extremely helpful and immediately re-flashed my program to 750 idle, but that didn't help.
So yes, I will miss the power and yes I will have to look for an alternative. In California, that means US tuner only because of our gasoline's lower Octane rating. The criteria will be:
1. Power delivery as spectacular as EVOMSit.
2. No change in sound.
3. Ability to switch back to stock, like GIAC's flashloader.
BTW, my experience reinforces the elegant idea of loading the tuned program to a spare ECU (very cheap -- only 650 or so at Sunset Imports here, plus another 200 to load Porsche original DME onto it, then the tuned program goes on top of this). The idea is not for warranty protection, but to cover "what if something goes wrong" scenarios. Within 15 minutes, my car has the original ECU back on and the beautiful sound of Cargraphic is back in all its glory. 
BTW, I found out I DID have a picture of my car at idle rpm -- the all important shot at 997 miles!
--
Regards,
Can
997 Turbo + Bilstein Damptronic ( Review and Pictures ) + ECU Tune ( ??? ) + Cargraphic Exhaust ( Oh heavenly noise! 
)
); that is now gone. And the character of sound is a more high strung note, perhaps good for others, but I can't stand it.
with me,and also if i'm alone on the car i have the problem that the car jump and can't follow the road...
)
