Relief/Diverter Valve
The relief valve maintains a constant air pump pressure of 3.8-5.7 psi (.27 -.40 kg/cm2 ). Excess pressure is vented to atmosphere. The diverter valve switches air injection from the exhaust manifold to atmosphere during deceleration. This reduces backfiring. When intake manifold vacuum rises above 8 in. Hg, the diverter valve closes and diverts air pressure. A calibrated air bleed in the diverter valve gradually opens valve and air injection is resumed.