Simplify the following text for a Grade 8 native English-speaking person.
Original: This design was very influential for racing engines as it featured for the first time dual overhead camshafts ( DOHC ) and four valves per cylinder , a layout that would become the standard until today for racing inline-four engines .
Simplified: It was the first to use dual overhead camshafts ( DOHC ) and four valves per cylinder . This became the standard design for racing inline-four engines .