Modern turbocharged cars are capable of making much more torque than HP. This is because the turbochargers are small sized to reduce turbo lag. In addition, the exhaust manifolds are also very small to further reduce turbo lag. The engine is designed around the lower boost and smaller turbochargers so the compression is too. The higher compression also improves CAFE corporate average fuel economy thereby reducing gas guzzler tax making the car less expensive to buy.
The recipe to making a lot of power without breaking your car is to increase the HP a lot more than the torque. The problem is, when you increase boost with software, the torque will go up a lot more than the HP because of the issues mentioned in the first paragraph.
For example, the 4.0L Mercedes AMG V8 will make 689 lb/ft torque and 596 HP. This is not a Mercedes problem- almost all modern cars react the same way when the boost is turned up. We would really like to have the opposite: 596 lb/ft torque and 689 HP.
The only way to accomplish large HP increases without large torque increases is to change hardware. With a larger intake, larger turbochargers and software we can make 680 lb/ft torque and 650 HP.
With a larger intake, larger turbochargers, software, larger exhaust and compressor housings, larger exhaust manifolds and more efficient heat exchangers, we can make 680 lb/ft torque and 700 HP.
With a larger intake, larger turbochargers, software, larger exhaust and compressor housings, larger exhaust manifolds, more efficient heat exchangers and a rebuilt engine with lower compression and ported heads we can make 680 lb/ft torque and 750 HP.
All of these examples are on pump gas with cats without meth injection!
Most people believe that it is necessary to remove the cats and put on down pipes to make big power. There is so much back pressure in the exhaust manifold and turbine housing that the down pipe makes very little difference in the power output. We ran a test with two different BMW’s- an F10 M5 and an F80 M3- and removal of the cats was a gain of less than 10HP for each car. The pollution is exponentially higher as well as the hassle in getting smog-test makes this modification not worth it.