Auto Racing: engine build, parasitic friction, torque wrench

Question
It's me again Matt. I seek your advise based on your vast experience on engine building. For my 4-cylinder 1275cc A-series British Leyland engine, I normally torque up the main cap at 60Ib/ft and big end cap at 33Ib/ft in accordance to the manufacturers recommendations. It just occur to me, when the job is done, is there any way I can check for any abnormal high spots at the bearing/crank pin journals or piston to bore clearance just by turning the crankshaft in the block with a torque wrench prior to fitting the head and the timing chain? What should the torque reading be if the reciprocating parts are all in good condition and the clearance are not interfered by any high spots? This would then give me double assurance that the re-build is truly OK.

Answer
First make sure to torque the caps in steps. If 60ft/lbs is the goal, start by torquing all the caps to 20ft/lbs, then 40ft/lbs and finally 60ft/lbs. This gives the bolt a chance to normalize. I also recommend using a moly lube under the heads and washers of the bolts. This removes parasitic friction during the torque process and makes for more accurate readings.

As for binding, this should be checked during trial assembly. You can coat the bearing journals with dykem blueing, assembly the parts, make a full rotation then disassemble to see where the dye has been rubbed off. Youc an also use a dial type torque wrench to measure parasitic drag. Keep an eye on the dial as you rotate smoothly through a complete rotation. Any spikes on the dial will indicate a bind. The torque spec varies from assy to assy, so watch the dial for drastic changes.