We brought the Grocery Getter out in 1996 with three 1972-1974 455 stock blocks. Using Program Engineering caps. The crankshafts were stock Pontiac N cranks, carefully prepared by me with no surface treatments, just nice oil holes and large radius. Lots of tuning errors with the nitrous. Lots of time spent learning the ignition timing the engine really wanted. Even a quarter mile run starting in 2nd. gear with all that nitrous when a shift linkage part failed. Never made the kind of power Marty made, but I would argue, we may have been just as abusive to the block. We were right at 1000 HP which was allot in those days. All three blocks did eventually fail and they all failed in the same area. Right up the oil passage at the #2 oil feed drilling from the main saddle to the cam bearing. At least for us, that was the weak spot in the 455's. Overall, the Pontiac block is very tough. By the way, no lifter brace in any of the blocks. Roller cam though with .850 lift and 260 lbs. on the seat back in those old days. We also ran our blocks unfilled. Didn't want the weight, didn't want the bore distortion, did want the cooling.
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