sadly i have only ~50% vacuum with 1.7 than 1.6
megasquirt also states, that 4 throttles does not give enough vacuum to work with MAP
For me it's a bit strange, because the combined vacuum of the 16V engine is enough to operate
the mechanical fuel pressure regulator valve, as far as I can tell the same regulator valves
were used on the 8V and 16V engines within the Alfa 33 serie (except the 1.4 IE
with IAW injection). And if a mechanical regulator can be driven, a MAP sensor, containing no
moving parts shouldn't be a problem for the engine either. Bit this is just my opinion
For the 1.6 engine I don't have the max advance data, but it was 32 degrees on the 1.7 IE (8V)
engines @ 5250 RPM, measured with WOT. Beyond this RPM, the advance wasn't increased further.
Even if the advance curve is within the factory specs, detonation could occur when the
mixture is too rich for the actual engine conditions, so I think the ping problem can be approached
from the mixture side as well.
Please let us know your further results and experiences