By RICHARD TRUETT | Automotive News DETROIT -- Ford Motor Co. has no intention of letting the new 500-hp Dodge SRT-10 keep the title of world's fastest truck. But John Coletti, director of Ford's Special Vehicle Team, acknowledges that automakers have hit a wall on how much horsepower they can give a vehicle. So the automaker will make the next-generation Ford F-150 Lightning pickup go faster by removing weight and improving handling. "In the next generation, we've got to worry about efficiency, weight and better control," he says. "You can get great power-to-weight ratio without a fountain of horsepower." Until the Ram SRT-10 pickup debuted this year, the Lightning had been the unchallenged leader in performance trucks for more than a decade. But in February, the SRT-10 clocked a record speed of 154.587 mph. Ford SVT engineers have experience in reducing weight with the 2002 Mustang Cobra R, a version for performance enthusiasts. Strong, lightweight materials such as carbon fiber, magnesium, aluminum, ceramics and plastics can substitute for steel parts without major re-engineering. Coletti says lighter parts and better-handling suspension systems might not come simultaneously. "You'll start seeing it in incremental steps," he says. "Now that we have the engines where we want them, the question is what do you do with the rest of the car? Clearly you have to start looking at the weight aspect of it. If I could take 300 or 400 pounds out of the car, I wouldn't have to add any more horsepower. It would just be an incredibly faster, better handling, better braking car. All the attributes would improve." Coletti believes automakers risk attracting attention from government regulators and the insurance industry by constantly increasing horsepower in their performance-oriented vehicles. In the last two years, the number of vehicles with engines producing 400 hp to 500 hp and more has grown quickly. "The focus now has to be better efficiency and weight reduction," Coletti says. In the heyday of the American muscle car in the late 1960s, only a small number of limited-production vehicles made more than 400 hp. The ratings of most Pontiac GTOs, Ford Mustangs, Dodge Chargers and Chevrolet Corvettes were in the 300-hp to 375-hp range. Today, there are at least 14 cars and trucks with at least 400 hp. Says Coletti: "We're hitting the limit."