The crank used was one of the early 330 Olds forged-steel cranks. Coveted for their strength, the 330 cranks were quite popular to drop into small-inch engines. Dale spent a bit of time modifying and lightening the crank: "I took 3 pounds out of it. They're pretty hefty to start with. It weighs like 56 pounds, it was 59 when it was stock." Since modifying the SFI-mandated flywheel was out of the question per EMC rules, Dale also had to re-drill the bolt pattern on the rear of the crank from the oddball 330 pattern. After lightening and resculpting the shaft, it was balanced to a set of Eagle ESP Featherweight Chevy-style H-beam rods. "I went with the longest rod that was still within budget at 6.250 inches. Barely attached to the rods by a set of paper-thin 71 gram wristpins are some custom Ross full-round pistons. At the time the pistons were ordered, Ross didn't have the shape of the combustion chambers to go off of, so they were hand-tailored to fit once they showed up. With a small dome and the pistons sitting just out of the hole, it wasn't hard to come up with 10.4:1 compression. To prepare the block for those pistons, Dale made a custom hot-hone torque plate, allowing 125-degree water to pass-through the engine as it was being finish honed. That brought the engine to an honest 316 cubic inches. After the short-block was assembled, they took a torque wrench to it and were pleased that it only took a mere 7 lb-ft to turn it over.
At a passing glance, the casual observer more than likely wouldn't notice the size of the lifters in an engine, but when it is torn down next to another GM block, it stands out that the lifters sure look awfully big in this little 307. A little digging revealed that during the '80s, Olds moved into the world of hydraulic roller cams and used a big .921-inch diameter roller lifter. This made it legal to use lifters big enough to make Mopar guys jealous, even if they did have to use flat tappets per the rules. Further block details evolved as the Robinsons drilled small holes in the lifter valley to allow oil to fall directly on the flat-tappet camshaft. Also, raised vent tubes epoxied into the lifter valley keep the crankcase pressure equalized between the upper and lower end of the engine.
The cam that was used to motivate the mondo lifters was a COMP Cams grind using the MM Mopar lobes designed specifically for large-diameter tappets. The advantage here is that the angular relationship between the tappet and the cam lobe allows the cam to whang open and close the valves-technically speaking that is. "Looking back now, I wouldn't have gone that big on the exhaust lobe. I think I over-exhausted it."