Originally Posted by Smoked88GT
Heard it a few times and wanted to know what it meant to blueprint the motor. Thanks
Balancing & Blueprinting is nothing more than machining different engine parts to specific tolerances. Balancing
To balance a V-8 engine requires 50% of reciprocating weight plus 100% of rotating weight, for a V-8 engine. Reciprocating weight
: Piston (1), rings (1 set), wrist pin (1), and small end of connecting rod (1). Rotating weight
: Big end of connecting rod, rod bolts & nuts, rod bearings, & oil supply to crankshaft bearings. Because there are two rods to each jounal then the rotating weight is x 2.
The pistons are all machined to weigh the same. The big end of connecting rods and small end of connecting rod are machined to weight the same (separately). Then the weights of the pistons, big end of connecting rods, small end of connecting rod, one set of rod bearings, one set of rings, one wrist pins and oil weight (usually 6 grams) is recorded and the bob weights are made up from the formula for the type of crankshaft being balanced. Then the bob weights (4 for a V8), dampener, flywheel (flex plate) are bolted to the crankshaft and spun to balance the left side and the right side of the crankshaft. Then spun with the left side and right side coupled together to make sure the crankshaft is still in balance.
The crankshaft is either welded on the counter weights (or heavy metal installed) or drilled on the counter weights (left and right) to bring the crankshaft into balance. Blueprinting
To blueprint an engine consists of several machine shop operations including but not limited to:
Bore & hone cylinders (usually w/Deck plates) and honed to the correct clearance.
Line bore or line hone the main housing bore in the block. (Or at least check to see if the housing bore is within the correct specificaions).
Re-size connecting rods (big end & sometimes small end).
Turn & index crankshaft.
3 angle valve job cylinder heads (to a specific width & place on valve face).
Fitting valve guides to a specific clearance.
Setting up valve springs to the right installed height & pressure, both open & closed.
Surfacing block and cylinder heads straight & with the right RMS finish.
Race engines require even more blueprinting----such as; cc'ing heads, machining for exact deck, block clearancing for crankshaft, & cam to rod clearance, porting & polishing, shot peening, heat treating,---the list goes on & on.