Will never peg. Sensor will support over 800HP when installed in a 3" housing. Updated sensor curve has been engineered to maintain perfect idle resolution even when used on vehicles making under 300HP. This sensor can be used in any housing from 2" to over 5". It can also be used for blow-thru or draw-through configurations. Limited lifetime warranty. This is the last mass airflow sensor you will ever buy. *Requires 05+ Ford maf connector *Requires computer tuning *Can be used on any 0-5V maf system with computer tuning *Transfer function generating software tool available for FREE download