The RDX uses a turbocharged 2.0-liter engine similar to those in the Accord and the Civic Type R. In stock form, it makes 272 horsepower and 280 pound-feet of torque. With Hondata's Stage 1 tune, the company says that horsepower increases by about 10 across the rev band. Looking at the dyno graph, it also appears that peak horsepower increases by about 5 horsepower, and peak torque is up by about 15 pound-feet. Peak torque also appears to arrive sooner, and most of the torque curve seems to be up by 10 to 15 pound-feet. The increases in power and torque are available in all four of the RDX's drive modes.
The Stage 2 tune increases power torque even more in Sport and Sport+ modes, and keeps Snow and Comfort modes at Stage 1 settings. Peak horsepower looks to be up about 10 over stock, but the mid-range sees as much as a 28-hp increase. Peak torque sees a huge jump of about 45 lb-ft over stock based on the dyno chart, and it's available even lower than the Stage 1's peak torque.
If this all sounds good to you, you can order up a Hondata FlashPro computer for your RDX right now. It costs $695 and comes with the handheld computer for uploading or removing tunes. RDX owners in California should note that neither tune is currently CARB legal.