Question

What is the value of the valve overlap, for a smooth idle and healthy low rpm torque?

(a) 0

(b) 40°-75°

(c) 1

(d) 80°-150°

This question was posed to me during an internship interview.

Asked question is from Variable Valve Timing topic in section Valve Timing Technologies of Automotive Engine Design

Answer 1

Right answer is (a) 0

For explanation: For a smooth idle and healthy low rpm torque we need to have zero valve overlap between the inlet and exhaust valve. Hence, 0 is the right answer.