Quote:
Originally Posted by TitaniumTT
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Turbo Control Valve - TCV located in the exhaust Mani - allows the full exhaust of the rear rotor into the 2ndary turbo
Charge Control Valve - CCV - Located after the 2ndaries compressor to keep the primary from backspooling the 2ndary
Charge Relief Valve - CRV - Vents the 2ndaries boost until it's ready to come online.
Pre-Spool Valve - PSV - works like a wastegate to send exhaust energy to the 2ndary to start spooling it up.
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So we played with the CCV, opening it earlier or later proved to make the biggest difference in the reponse. We would either get a HUGE surge in torque, which just felt odd, or a slight dip during the transistion and then boost built again. This is what we opted for. After 21 runs (and 101 runs total) it seemed like we were chasing our tails and not getting anywhere, so we decided to call it for the night and head back after some street tuning.
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Very interesting. I've also got a standalone that will allow me to control these valves independently, and so far I've got the CCV, CRV, and TCV solenoids all switching at the same RPM (4000 works well so far). At low RPM, the WG solenoid is about 90% duty and the PSV is used for boost control.
Your post above suggests you might be opening the CCV before or after the TCV and CRV?
By the way, regarding TPS-based boost control, I've heard of tuners using this as a way to compensate for throttle airflow saturation. If your throttle allows about the same airflow from 70-100%, increasing the boost target at 80, 90,. 100% is one way of giving the throttle a nice linear feel. I've tried this on my car and the feel is pretty nice... I imagine it's a bit more important with big-power cars like yours, mine isn't even putting 300 to the wheels.