Secure Vehicle on Dyno and Initial Power Measurement

What happens here

Upon returning to the shop, the GMC Yukon XL is carefully driven onto the Dynojet dynamometer. Once positioned, the vehicle is securely strapped down to prevent movement during high-speed runs. The host manually checks the tension of the straps to ensure stability. An initial dyno pull is then performed, where the vehicle accelerates on the rollers. The engine's sound is monitored, and the dyno software records preliminary power figures. The first pull records 397 horsepower (HP) and 432 foot-pounds (ft-lb) of torque, with the tuner noting a lean air-fuel ratio.

Goal: Measure baseline horsepower and torque on the dyno.