| I found this information very helpful in assessing the condition of my current conrod bearings running clearances although I haven't yet measured anything. From the Forced Induction Performance Tuning book: Ideally a [conrod] bearing should show wear over about 65-75% of its surface. If it is showing contact almost up to the parting line, fit bearings with more eccentricity, but when the contact area is too short, bearings with reduced eccentricity are called for. When you have calculated the running clearances for each bearing you will probably find that some have a little more than you want, while others may be a touch tight. If the engine is a popular unit for competition use, the bearing manufacturer may have special 0.001 in undersize and oversize bearings available. Using just one half of such a bearing allows the clearance to be opened up or closed down by just 0.0005m. When mixing a 0.001 in undersize shell with a standard size shell the recommended orientation is to fit the shell with the thicker wall in the upper position in a big-end and in the lower position in a main bearing. After ensuring that all the bearing housings and bearing shells are perfectly clean and dry, fit the shells and check oil hole alignment; any misalignment should be corrected using a small round key file. After filing, carefully dress the steel back of the shell to remove any metal fraze. Next, coat all the bearings with engine oil and fit the crankshaft (do not use a 50-50 mixture of oil and any substance like STP). Fit the main bearing caps in their correct order with arrows facing the front of the block and gradually tighten them down. Before final tightening, the crank should be tapped to each side with a soft hammer in order to line up the bearing caps. Now check the crankshaft end-float: it should be within 0.004-0.006in with a cast-iron block. If the clearance is more than thiv 360 fit thicker thrust washers.
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