ko tunggu otai 4AGE datang jengok ni thread
bagi aku yang tidak otai ini
TVIS yang 1st and 2nd generation of 16V 4AGE.. pa tu? Toyota V stand for? Valve ka Variable?Induction System.tapi system ini melibatkan intake, manifold system..
ni aku copy paste ni..baca lah
Toyota Variable Induction System, or T-VIS, is a variable intake system designed by Toyota.
It improves the low-end torque of high-performance, small displacement four-stroke internal combustion engines - by changing the geometry of the intake manifold according to the engine rotation speed. The system uses two separate intake runners per cylinder, one being equipped with a butterfly valve that can either open or close the runner. All valves are attached to a common shaft which is rotated by a vacuum actuator outside the manifold.
The engine control unit (ECU) allows vacuum into the actuator by powering a solenoid valve
when the engine rotation speed is below 4,200 rpm. Above this engine
speed, vacuum is cut off and a spring inside the actuator causes the
butterfly valve to fully open. The theory behind the system is that in
the lower engine speed band, the speed of the intake air will be
increased because the intake runner cross section
per cylinder is smaller. However, when engine speed increases, the
second runner is opened, decreasing airflow speed, but increasing the
airflow volume, better matching the engine's airflow needs at higher
rpms. With modified engines (more flow) it may be desirable to have the
T-VIS open earlier than stock, because it begins to restrict the
airflow at a lower rpm, since the airflow per rpm is greater with
upgraded turbochargers, intake, and exhaust systems.
Subject: pa beza 4age tvis ma 4age yg lain...tolong!!! 
11/3/2010, 12:10 pm
