The Cup was 300 at JZM, that is correct. The revised spec, this from RS Tuning in Germany and help with technical translation to my pal Jo:
> Umbau auf Sportkatalysator
Sportscatalyst (standard is 1000 cells the sports is also called 100cell sports katalyst sometimes)
> Anpassung der Sauganlage
Adaption of the Intake (see later that is the 993 part)
> Vergrößerung der Drosselklappe
Bigger "Throttle Flap" - kind of
> Montage eines Sportluftfilters
Sport Airfilter
> Montage eines Cup-Rohres
Cup-Tube, replaces the Muffler between the two sides of the outlets with just a plain tube
> neue Nockenwellen
new (NOT saying different of other - NOT saying same either - just saying "new") Camshafts
> Bearbeitung Zylinderköpfe
work done on the cylinderheads (probably means redoing the intake and outake, making them nicer, grinding away edges, polished etc.)
> Luftmassenmessung Typ 993
The sensor for measuring the mass of the air passing through the intake (as with the 993 model) rather than the amount (as standard with the 964) - AFAIK this goes along with the bigger throttle flap and the 993 intake as basically they fit the 993 intake with mass sensor and bigger throttle flap. This alone does get you close to 300 hp I was told.
> Programmerstellung auf stationärem Prüfstand
reprogramming the Motronic on a stationary engine test stand. This is good as the cheap guys just fit the 993 parts and put a standard chip in, whereas I was told that the tuning should ALWAYS include a reprogramming on a tests and making sure your engine is optimized and not just running an average of-the-shelf optimized Motronic.
With this spec, I have a bench test readout of 306bhp in the car 's history.
However, as you know, last year I ran number 5 bearing, with associated damage, so the engine was rebuilt. Craig at GT1 found a lot of non-standard gaskets and washers, plus sealant, which may have blocked oilways and led to its demise. He has rebuilt the engine 'by-the-book' and I can only assume that this was not the case before.
It's now fitted with new pistons and barrels and many other replacement parts, so I can only assume that the extra 23bhp found at G-Force is down to the rebuild.
Incidentally, they did two runs with a low ambient temperature that gave 318bhp, and one with a higher ambient, that, to their surprise, gave the higher reading.
Thye told me that 964's are notoriusly difficult to tune on the rolling road due t the high intake temperatures and in the summer they have had to wait until 11pm to get the temps down!!
Rgds
Mel