The last Mopar Muscle magazine had an article about Arrington Engines in Martinsville, Virginia. They offer complete kits for 426 and 440 motors based on the 6.1. The 440 comes with 575 horsepower. Kits contain everything to make them work in your car. Wiring harness, sensors, etc. That's a modern 440 cubic inch Hemi. They show a dyno sheet of each engine with 90mm throttle body. The 426 has peak horsepower at 580 and torque at 539. The 440's horsepower peak is 628, torque 596. Looks like they have a website at
www.shophemi.com.