[citation][nom]alextheblue[/nom]Well, this 3.6L is actually pretty light, and gets pretty good mileage for the size of the vehicle. If you take your 4 banger, add in the turbo, extra tubing, and intercooler, and a 2.5L turbo wouldn't be *that* much lighter. Even though I like them, smaller turbo engines aren't automatically better in every situation, either. GM has turbo engines in their lineup, including the powerful 2.0L turbo in the GS Turbo - lots of HP and torque (I think 270/295 stock), no turbo lag whatsoever. A slightly higher displacement (like the 2.5L you stated) would have made more power than even this engine. But the GS Turbo is a smaller lighter vehicle.Yet their engineers chose this direct injected naturally aspirated V6. Maybe these engineers know what they're doing? Maybe there's more to a car than just power specs, or for that matter more to an engine than just power or fuel economy alone? The DI 3.6L has a proven track record, for starters. It's a solid engine, and it's a fairly big car. Maybe in their testing the 3.6L had better characteristics or durability for the kind of workload/RPMs it would be under. Maybe it was quieter, and smoother. I think anyone in the market for a luxury XTS would want a vehicle with a nice, even throttle response and a smooth engine. Noise, vibration, harshness. NVH - very important to your typical luxury car driver.If you want a mean little turbocharged Caddy, keep an eye out for the upcoming little brother ATS. Built on Alpha platform, with available turbo 2.0L. I should also note that the DI 3.6L in the Camaro now has improved heads and produces 323HP stock. After a couple of years they may deem it a suitable upgrade for the XTS, if it doesn't hurt NVH characteristics.[/citation]
+1 Excellent points sir. Yea I see a lot of the econoboxes on the market that get ~40MPG HWY EPA and some have 1.8L naturally aspirated engines, others have a 1.4L turbo engine, both get about the same MPG ratings and close to the same HP. Perhaps the turbos get a tad more HP/Tq like the Chevy Sonic. But it's not clear if the increased complexity of a turbo is worth it, or heck, if DI with high pressure fuel lines is worth it.