Before the tuner’s adjustments, the D16 made around 200 hp with a slightly inconsistent (wavy) power curve. Sounds generous for a Del Sol, but that figure doesn’t really match the gigantic turbocharger inside its engine bay. The car also didn’t come with a matching timing setting.
The video goes deep into how this was achieved. In a nutshell, the tuning mainly involved increasing the boost pressure of the Del Sol’s turbo, finagling with the car’s timing, and setting its ignition timing. The tuner also replaced the car’s spark plugs and adjusted the car’s fuel-to-air ratio, among other things.
Note that this build is a customer’s car that came with various mods from the get-go. Apart from the large turbo from HunterTuned itself, it also sports an aftermarket camshaft, a beefier set of aftermarket pistons and rods, a Skunk intake, a 40mm wastegate, and MSD coils.