You'll find fundamentally two configurations to the 4A-G cylinder block with some minimal variations with the 5 vale variations. In all cases they have got these traits in typical. The cylinder block around the 4A-G is made from Solid iron alloy. You'll find 5 primary bearings held with two bolts https://4ageforsale69022.blogpostie.com/48870653/4age-20v-itbs-fundamentals-explained