Now on to the block...
This thing was a mess! This is how the block looked when it showed up at our shop. The customer said it was sitting in his yard for over a year. So we knocked off the mud and grass and then it was time for a good cleaning in the hot tank.
We placed it in our Hotsy hot tank which sprays the block with heated degreaser solvent which removes the grit, dirt and rust.
Then we placed it in our boring bar and bored it .030 over stock.
Then it was installed in our power honing machine which uses stones to sand the cylinder walls straight.
This removed any tapering and/or cut marks caused during the boring process. It also creates cross hatch marks that file the rings, helps seat them into the cylinder walls and to seal the combustion. Ring end gap size is important because too much creates crank case blow by. Too little ring end gap will cause the ring ends to butt together and cause cylinder scaring or the piston to break at the top ring groove.
Cylinder Bore Refinishing info via Hastings Rings
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On this particular engine, we used hypereutectic pistons which require a larger ring end gap of 0.008" per inch of cylinder bore. In this case the cylinder bore was 4.030", therefore the ring end gap would be 0.032".
Hypereutectic performance pistons will expand less than typical cast or forged pistons. Because of this and the wear characteristics of the hypereutectic alloy, you can run tighter piston to wall clearances which helps the engine run more efficiently and last longer.
Most engine rebuild shops try to get away with using the cheaper components and inaccurate, obsolete machinery to preform their work.
WE DON'T!!!
Got any questions?
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