Before finishing assembly of the engine, I checked all the cylinders with OTC leakdown tester. Six of them were within 2 or 3 psi of the accepted 15 percent leakdown rate for a newly assembled engine. Two cylinders had higher readings, one of them being more than 30 percent. Turning the engine over several times by hand fixed this, but not before I removed that bank’s head to verify that the piston rings had indeed been indexed correctly. After that, all the cylinders indicated less than 15 percent leakdown.