hmmm all very interesting hellish stuff that im looking forward to get rid of.
Correct me if im wrong Ross. but from what i understand Vacuum holds it closed, when you start to hit VOD/change over the vacuum is released and the spring opens the IACV. Air has to get into the solenoid "IACV" somehow and the only way is via the vacuum hose. Having the restrictor pill simply restricts the air getting into the solenoid thus slowing down the rate it opens.
[quote name='Rosssub said:
I have a spare B4 TMIC and IACV here, I\'ve been bench testing the opening speed. With a Vac hose connected to the IACV Actuator, applying Vac to close it. Then releasing Vac and timing how fast it opens. Then adding Restrictor Pills to the Vac Hose, to slow it down/restrict it.
IACV opening times:
OEM open 4mm hose - 0.15 seconds
2.0mm Restrictor Pill - 0.35 seconds
0.8mm Restrictor Pill - 0.85 seconds
I think extending the vacuum hose, using larger diameter hose or adding a collector tank would cause more of a VOD delay than anything else. This would cause the VOD/change over to occur slightly higher in the rpm where there might ? be more boost to handle spooling the secondary faster? Creating a similar but yet totally different result than the restrictor pill?