Turbo upgrades are available if you still need more power. You can expect gains of 60 to 80 horsepower (or more) in the higher RPM band after proper installation and tuning of a turbo-charged engine.
     

Unlike superchargers, which are belt-driven, turbochargers harness your car’s exhaust system to force air into the engine. Turbochargers consist of a turbine that is bolted into the exhaust manifold. When exhaust leaves the engine under pressure, it enters the turbine and spins it. The more exhaust, the quicker the turbine spins. The energy made from the first turbine brings a compressor into action, drawing air in from the air intake. The air is then compressed before it’s forced into the cylinders. 
     

It’s a good idea to add an intercooler into your turbo system if it doesn’t have one. When the turbine compresses air, it becomes super-heated. Hot air is less dense and thus has less oxygen. Intercoolers actually help increase horsepower by cooling the air and providing more oxygen to the engine. An intercooler looks a little like a radiator and works by taking the compressed air and cooling it. The colder air is more oxygen rich and dense when it is forced into the combustion chamber. If you’re buying a turbo kit, check to see if an intercooler is included.
     

What are some downfalls to turbo? Turbochargers are expensive. Expect to pay $3000.00 or more for a bolt-on turbo kit. This cost doesn’t include having your engine refreshed or rebuilt first and may not include an intercooler. You’ll probably want a professional to install it to make sure the turbo system integrates smoothly with your engine, as fuel injection or ECU problems arise. You’ll also want to tune it afterwards, which requires the engine being put on the dyno by a specialist. Expect to pay at least $80.00 an hour if not more. You’ll need at least an hour and up to four to get your engine working right. Turbo-charge engines require maintenance to run properly. Turbo requires a higher octane of gas to prevent pinging and other engine mishaps. The higher temperatures require an upgrade to premium coolant and a higher grade, turbo-rated oil that’s able to withstand the heat.