Well, finally got the C3 dyno'd. I realise that these figures cannot be taken too seriously and mainly I wanted to do this just to see what the fuel ratio mixtures were like etc.
After rebuilding the motor with new late model SC (204hp '83) model pistons and barrels (i.e. up from 8.5:1 to 9.5:1 compression ratio - I think the later figure is correct), I had estimated that the engine would produce in the vecinity of about 220hp. The graphs indicate a maximum of 127.1kw (170hp) at the rear wheels, which translates to approximately 180kw (242hp) at the fly wheel using a 30% drive train loss factor (I know, this figure is arguably lees for 911's). In any case, I am fairly certain that I have achieved around 220hp which is adequately up on the 200hp the car came with from the factory.
My only concern is that the AFR seems a bit lean early in the rev range, is this normal or something that should be looked into further. Later in the rev range, the AFR is about right (assuming 12.5% is perfect)?
Here's the graphs for you to asses:
Graph with AFR and Power
Graph with Power and Torque
