Why does the 2010 Town Car only have 239 horsepower?

Generally, as an engine gets bigger, its horsepower increases. Horsepower doesn't just depend on the size of the engine, but also whether it is turbocharged or supercharged. But are these the only things that horsepower depends on, or are there more variables? For example, the 2010 Lincoln Town Car has a 4.6 Liter V8, but it only has 239 horsepower, whereas the 2010 Lexus LS 460 also has a 4.6 Liter V8, but has 380 horsepower. The Toyota Camry XLE also has a regular 3.5 Liter V6, and has 268 horsepower, which is still more powerful than the Lincoln Town Car. The Chevy Impala also has a 3.5 Liter V6, but only has 207 horsepower. The Subaru Impreza WRX STi has a 2.5 Liter turbocharged engine with 305 horsepower, which is more powerful than an engine that is almost twice as large, the 4.6 Liter V8. So what accounts for the huge differences in horsepower between engines of the same size that are NOT turbocharged? And what exactly is it about the Lincoln Town Car's 4.6 L single overhead cam (SOHC) engine that makes it so weak (low horsepower)? I would not at all mind a technical explanation.

Because no matter how hard the imports try, they will NEVER make a Full Size Solid Axel Rear Wheel Drive V-8 American Sedan. The flip to that is American Car Companies will never make a Camry. The 4.6 Town Car is made for one thing only, get 5 people and their luggage to the airport with plenty of room with a nice comfortable couch like ride. Not horsepower. The Camry and the other cars mentioned are not full size cars, and are designed completely differently to fit the Liberals needs as necessary. Now if your response is why have the Town Car then, if it doesn't meet the need of people, well, I will tell you it does, there are plenty of people who love these cars. If you next statement is well I need to change and conserve, then go F!@#$ Off you Liberal b/c this is a free country and I will do want I want where ever. I shouldn't have to pay more b/c my car is heavier, or that it consumes more fuel than most, nor should I have to pay a yearly Environmental fee either. If you disagree I dont know what to tell you.

The Towncar has low HP because, like it was touched on before, is made to be a quiet, comfort ride. It is designed to have maximum low end torque. It's a big car. The drivers don't want to have to rev the snot out of it to get it going.

If you do a few minor tweaks (CVPI airbox, MAF, and Zip Tube) it will be 250HP, same as the Police Interceptor model Crown Vics without sacrificing that much needed low end torque but will really only make a difference at high RPMs which it is likely not going to be in very often.

In other words, the engine is not made to rev up into the 5000RPMs, just stay calm, cool, and collected at around 1700-3000RPMs to keep things quiet for the passengers.

I'd be interested in seeing the torque curves values for those other cars you listed. I can easily get my car (same platform and just earlier model of engine rated at 200HP from factory) up to 50MPH or so without having to go past 1/8 throttle and hardly hear the engine try thanks to the large amounts of torque from the SOHC setup. Logging it, I doubt it'd go above 2300RPMs.

BTW, they do have these same engines with 3 or 4 valves. They are used in the Mustang. The 4V was used in the Mercury Marauder and produced 302HP from the factory but the 3 and 4 valve motors also suffered from slightly lower low end torque figures and instead went for high end power.

Horsepower sells cars, but torque wins races.

this car is not meant to have a lot of horse power, it is not a sports car, it is a luxury well built american car. I don't know why you are comparing it to piece of shit jap cars. obviously if lincoln wanted to they could produce at least 300 hp from this engine. for example the 94 mark viii had a 4.6 and produced 280 hp and 290 with lsc in 96.that was almost 20 years ago imagine how much they could produce now? Not everything is about speed, its about comfort, reliability, safety etc, which the towncar has all of and exceeds Japanese predecessors in.

''Let it Be'' ,it' s a 1st class Taxi service with great fuel economy.