[Greenv8s]

As far as I understand it, the theory is that upstream water injection enables the compressor to achieve greater mass air flow (by reducing the temperature rise and loss of density that occurs inside the compressor).

I don't think it is possible to prove this theory by comparing with/without water injection, because we already know that water can be beneficial wherever it is injected.

The only way I can see to prove the theory is see whether we get more mass air flow using WI immediately upstream of the compressor or with the same amount of WI immediately downstream of the compressor. By concentrating on mass air flow at the compressor I think we can avoid complications from other changes in the tune. To be conclusive, we would need to ensure that a similar amount evaporates in both cases. I think it might be possible to achieve this by using only a small amount of WI so that we get total evaporation in both cases, does this seem reasonable? Since mass air flow is the thing we are looking for, it would make sense to measure that directly if possible, rather than trying to infer it from changes in temperature and pressure or detonation, net bhp etc.