This .90 size engines connecting rod was made of hardened CPM 3V steel. This alloy was susposed to be very similar to hardened AISI S-7. On the third dyno test at 32,000+ rpm, the connecting rod failed. Mechanical failures of parts at these rpm's is always instantaneous & severe! Notice that the short pin which drives the induction valve is completly sheared off. The crankcase was cut to remove inner parts.
