Many auto enthusiasts would say that the only competition Porsche has when it comes to performance excellence is itself.

Perhaps that's why the company outdoes itself with one hot car after the other -- and this summer is no different.

Just in the last few months, the company has introduced the 2007 911 Turbo, powered by an amazing 480 horsepower, twin turbo 3.6 liter Boxer engine. The engine has the distinction of being the first gasoline engine used for variable turbine geometry. The 911 turbo equipped with the optional five speed A Tiptronic S automatic transmission hits 60 mph in just 3.4 seconds.

When you have all that power, weight balance and distribution are crucial, and that's one of the reasons the 911 Turbo comes with an all-wheel drive system.

Porsche says styling changes on the car are more evolutionary than revolutionary. "The modified front end features tautly drawn cooling air inlets, widely spaced and deep-set fog lights and new LED indicators situated in the lateral air inlets," a Porsche statement on the car says.

Meanwhile, around back, "The redesigned wing spoiler has been aligned to the wider profile and slopes downward at each end to nestle the rear fender's contours."

The car goes on sale this summer at a price of $122,900.

The other big news from Porsche comes from the 2007 911 GT3, a car that Porsche says is its most powerful non-turbo 911 in history, with a 415 horsepower, naturally aspirated Boxer engine. It will reach 60 in 4.1 seconds and its top speed is 193 miles per hour.

For the first time, Porsche says, the 911 GT3 will have an active suspension with two modes, one for driving on normal road surfaces and on for the race track.

The GT3 costs $106,000 and will be available beginning in August.

Fuel mileage figures had not yet been calculated for these cars.