Download free The Toyota Engine 4A-GE Block Reference Manual.pdf

This reference manual of Toyota engine 4A-GE. Great article made by Richard White, about the famous Toyota famous engine, 4A-GE that is widely used to empower the Toyota Corolla.

There are basically two configurations on the 4A-G cylinder block with some minor variations with the five vale versions. In all cases they have these characteristics in common. The cylinder block on the 4A-G is made of cast iron alloy. There are five main bearings held with two bolts each that are 2.70 inches apart. The bores are 87.5mm center to center apart. The weight of the bare block with main bearing and bolts are approx. 76Lbs. (late model 4A-GELU with Oil squirter/coolers) and 67.5Lbs. (4AC type). The stock bore diameter is 81mm. It can be bored out to as much as 83mm. However it is not recommended beyond 82mm because the siamese bore arrangement leaves very little head gasket material between combustion chambers for sealing high combustion pressures and the cylinder wall thickness begins to thin. These thin areas also increase the likely hood that cracking could develop under high thermal loads. Likewise the maximum stroke will not only be limited by the rod lengths (122mm) and deck height (191mm); it will also be limited by the connecting rod bolt to block clearances. Using any stroked crank over 79mm will require grinding on the block with a maximum stroke approaching 81~ 82mm. Note for those using the 7A block and crank you will have 85.5mm of stroke and 206mm deck height.
Blocks from the high compression AE92 (4A-GELU) and supercharged MR2 (4AGEZ) are stiffer/stronger than the other normally aspirated blocks and have proven to hold up well over 200hp. Blocks from earlier engines should be capable of handling anything less than »130hp., since this appears to be where Toyota decided to redesign its blocks for higher output models. I suspect the margin of safety will decrease as output increases. Moreover, the AE92 (4A-GELU) with the high compression pistons have piston oil squirter/coolers, while US model AW11, 4A-GEZ (supercharged MR2s), did not come with them.

This pdf reference is available FREE at Dizons website, we merely collect the information, we are neither affiliated with the author(s), the website and Toyota brand nor responsible for its content and change of content.

Download free The Toyota Engine 4A-GE Block Reference Manual.pdf (9 pages pdf file, 0.3 MB).