The fourth-technology 4A-GE engine was manufactured from 1991 to 1995. It has silver cam covers with chrome lettering, hence the nickname "silver top". This engine another time options a very new cylinder head which employs five valves per cylinder instead of four. It works by using Toyota's Variable Valve Timing https://4a-ge-engine-for-sale58901.blogchaat.com/40029064/4age-20v-turbo-engine-for-sale-things-to-know-before-you-buy