That's not true. The position of either camshaft in a DOHC engine is sufficient to determine the point in the cycle. You don't need both. camshafts.
> That's an interesting point. Although in any four cycle engine the
> camshaft, or camshafts in a DOHC design, must turn at half engine
> speed, you're right that with a single camshaft every position of the
> camshaft corresponds to a single point in the cycle. You need the
> positions of both camshafts to get that with a DOHC. Good thinking! >