At last - a public statement from Steinbauer about how the P-box works, so no further conjecture is necessary :
"STEINBAUER modules do not change rail pressure. The desired performance enhancement is achieved by changing the injection duration, the same way the system was originally designed to operate. This also allows precise fuel control throughout the full rpm range of the engine. Injection duration is achieved by adding pulse width to a signal, i.e. at end of injection. This is not changing timing—that's best left to the factory ECU."
From http://dev.steinbauerusa.com:8888/gb/products/passenger/saab/9-5/5575/
I was just looking at their website yesterday. Anyone tried the 1.9 diesel upgrade? Also I could nt find a key for price codes?
So essentially its really just putting more juice in and that's all?????
Seems so.
Works, though - my mpg isn't any different with or without but the driving experience is quite markedly improved with it.