Thats part of the reason, and why the cams can't be interchanged, if they could they would have the same part#... exhaust valves open early before bdc on the power stroke to blow down the cylinder combustion pressure before the piston starts the exhaust upstroke... thats done so the piston doesn't start to re-compress the expanding exhaust gases, which rob power from the next cylinder's combustion / power stroke., valve duration effects overlap and exhaust reversion / and induction standoff.... saito's known for their aggressive cam profiles, they mimic RW engine performance profiles why I was surprised the prototype shared the same valve timing for both cylinders
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I only owned 4 saito's,. a .50GK, 1.30TD, 1.50s, and 1.80 NIB.... gave the 1.50s to a flying buddy, and sold the 1.80, I never had plans to used it, as I like the larger giant scale aircraft... I dislike the AAC's so I stopped purchasing saito... and they continue to disappoint with the 100TS having composite cam lobes.... otherwise they're nice performing engines.