I use the Federal Mogul narrow full groove main bearings and I make the cam oil the rockers full time, I restrict the oil passgae in the block to the roller rockers on motors with non Indy heads(they oil the rockers externally full time ) with a #6 brass set screw with a .039 hole in it that I drill with a numbered drill bit I have not and do not ream the main oil passages, have not seen a need for it I have a bunch of stock stroke motors and stroker motors, 3.91 to 4.5 stroke, with ths combination being raced and driven on the street with no oiling issues in 12 yrs My 518 C.I. low deck pump gas motor gets shifted at or above 7000 RPM on every run, I had the motor out and looked at the bearings this past winter and all of them looked great, it has around 85 runs on it plus 30 + dyno pulls and 300 + miles street driving It has a stock Mopar 6 pak(6 quarts inside) oil pan on it with the 3/8 stock oil pick up installed, I use 5W20WT Valvoline non synthetic oil also Motor made 727 HP with 710 Ft lbs. torque on Oregon pump swill on a DTS engine dyno, Indy SR M.W. ports, single 1050 Dominator on a Indy 400-3 intake, Comp Cams solid roller cam and 10.78 to 1 compression ratio. IHTHS