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About bwnunnally

Bruce Nunnally is an independent Blogger who writes Cadillac Conversations on all things Cadillac. Connect with Bruce on Google+

Autoblog would buy a Cadillac CTS-V before a Cadillac XLR-V

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In the Autoblog Garage: 2009 Cadillac XLR-V offers an interesting summary of the 2009 Cadillac XLR-V Experimental Luxury Roadster, V-Series. The blog has a nice selection of great images of the XLR-V.

A reasonable question that Autoblog asks is why would an enthusiast pay $100K for an XLR-V with a 443hp Supercharged Northstar 4.4L engine instead of roughly $60-65K (prices STILL not announced) for a new CTS-V with a 556hp Supercharged OHC V8?

S/C Northstar Engine

S/C Northstar Engine

I know at least from my personal perspective there are advantages and disadvantages of each vehicle. The XLR cars of course are 2-seat roadsters, with folding hard top convertibles. The CTS cars are full size sports sedans. I like to joke that the XLR is a Corvette chassis with a Cadillac engine, while the CTS-V is a Corvette Engine in a Cadillac chassis. Actually the LSA engine in the CTS-V is unique to the CTS-V (so far), but it makes a nice summary.

Engine Sketch

Engine Sketch

I agree that it would be fun if Cadillac had retooled and put the 556hp LSA engine in the XLR-V this year, but the 4.4L Supercharged Northstar is a jewel of an engine. Since both cars are faster than they have to be anyway, XLR-V owners may legitimately want the smoother power delivery of the DOHC VVT Direct Injected Northstar engine.

GM’s Rick Wagoner explains Government Technology Investments

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GMBlogs has this video from Rick Wagoner who explains the recent Government decision to make $25B in  loans available to automakers to help develop new technologies:

The Energy Security Bill of 2007 which established the new fuel economy requirements that the Automakers are responding to had built in financial support to assist Automakers in meeting the aggressive new requirements. The funding support passed this weekend is the funding promised by Congress.

2009 Cadillac CTS-V : Supercharging Ahead

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Hemmings Auto Blog has a nice blog on History of the Supercharger

I was delighted to see that ideas like small fans blowing into the carburetor were invented in 1902, very close to the birth of the automobile. Cadillac’s new 2009 CTS-V with a supercharged 6.2L OHV V8 makes 556 hp and 551 lb-ft of torque. Let’s talk about the supercharger.

CTS-V Supercharger

CTS-V Supercharger

The new LSA Engine in the 2010 Cadillac CTS-V uses an Eaton TVS1900 1.9L four-lobe roots type supercharger.

The TVS supercharger’s patented design features four-lobe rotors and high-flow inlet and outlet ports that greatly enhance thermal efficiency, deliver higher volumetric capacity, and enable higher operating speeds. The TVS supercharger is capable of running with a high thermal efficiency (up to 76 percent) across a very wide operating range.

All TVS superchargers have a 2.4 pressure ratio capability and a thermal efficiency that exceeds 70 percent, which enables more compact packaging and greater output.

CTS-V TVS1900 Supercharger Thermal Profile

CTS-V TVS1900 Supercharger Thermal Profile

The engine designation for the CTS-V is the LSA. The Supercharger is well incorporated into the design and presentation of the engine. In the cutaway below you can the supercharger just below the top beauty cover’s “Supercharged” lettering (that’s truth in advertising!):

CTS-V LSA Engine cutaway

CTS-V LSA Engine cutaway

Just on top of the supercharger in the image is this water to air intercooler. Supercharging the intake air compresses and pressurizes the air. This raises the temperature of the intake air, which is not desirable. The intercooler acts to reduce the temperature of the air as it exits the supercharger on the way to the engine.

CTS-V Intercooler

CTS-V Intercooler

The LS3 V8 engine in the 2009 Chevrolet Corvette makes 430-436 hp, depending on optional exhaust or standard, and 424-428 lb-ft of torque. So the LS3 engine in the CTS-V would have made no more than 430hp. The LSA Supercharged engine used in the Super CTS-V makes 556hp, a nice net addition of 126hp due to the blower.

With everything going on with the US Economy, I am not sure how many CTS-V’s Cadillac will sell this year at around US$60K a copy.  Have no doubt — the CTS-V is a Super, World-class if not World leading Sports Sedan.  I hope that Cadillac sells a ton of them, so that one can trickle down to the Caddyinfo Garage!