A torque plate MUST be used when the cylinder sleeves on an aluminum modular block are bored and honed!!! A torque plate is simply a thick plate that bolts where the head gaskets go and when torqued to factory specs, distorts the block in the same way that the cylinder heads would if bolted on. The aluminum block distorts more than the iron block when clamping forces act on it and if a torque plate is not used during boring and honing, the piston rings will not seat properly.
The machine shop owner didn't believe in using a torque plate and this is where our relationship ended. My deposit was put towards polishing the factory crank journals and hot tanking the block, and I starting searching for machine shop number two.
|A Torque plate for the modular 4.6 and 5.4 family made by BHJ.|