Ford Racing's GT-40X Cylinder Heads Install - Hustle And Flow
Here, you can see the GT-40X heads were worth 24 hp and 22 lb-ft of torque at the wheels. We liked the improvement across the entire powerband, and gains were likely to be had below 3,000 rpm, but that's where we have to start the dyno pull, otherwise the AOD will downshift. Since we're still using the stock cam, the powerband has basically remained in the same place, which keeps the torque peak low and in a very usable range. View Related Article