GUII ZD30DI Wgn
I'm not concentrating on pressure, I could run higher boost quite easily and in fact have during testing, but I'm pulling bloody good torque down low and bloody good rwhp at a setting I'm happy with as a good reliable setting. I can pull away from 1200rpm in 4th gear and it pulls hard from 1500rpm.I read everywhere on all sites people focusing on pressure and PSI although what matters is just the volume of air and therefore to maximise the MAF value. I strongly encourage everybody to only look at this. Our original MAF sensor is quite accurate. I have two, and both give the same tension at 0.05V accuracy. so the reading is accurate.
At 2300RPM in third gear, my MAF exceeds 4V, and the boost is no more than 17psi. ( and since I have no remap, I keep the MAF tension seen by the ECU at 3.75V. ( and 3.9V below 3000RPM).
The pressure builds up continuously and gently vs RPM, and MAF goes up quick and nice too.
To achieve that, I get the actuator to "dance the rock" (purple line). The best non-electronic solution (i.e pneumatic) to match this uses three valves ( One Needle, one Dawes set to open very very early : +300mbar, followed by a second needle to regulate the quantity of pressure going through to the vacuum hose). Unlike the Dawes-Needle arrangement which keeps the vanes closed up unitl the dawes opens. In between you see pressure, but much less air ! and on top you build back-pressure).
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