If there's one thing to be said about the Cadillac Catera it's this: it was a great Opel but not a good Cadillac. The German-built Catera was originally the Opel Omega, a sport sedan with an overall solid reputation in Europe. It went on sale in the US as the rebadged Catera for the 1997 model year but failed to catch on for numerous reasons. For starters, Cadillac wasn't the appropriate brand because a majority of its customers at the time were older and not so interested in a European-designed and engineered sport sedan. They preferred larger and more comfortable sedans and coupes like the Seville and Eldorado.

But GM needed to attract younger buyers to Cadillac and the Omega offered a quick and cheap way to try. Like the Omega, it came powered by a naturally aspirated 3.0-liter V6 with 200 horsepower, paired to a four-speed automatic transmission that directed power to the rear wheels.

There was really nothing American about the Catera, other than its Cadillac badging. Its engine was built in the UK, transmission in France, and final assembly took place in Germany.

Cadillac's US marketing campaign claimed it was "the Caddy that zigs" and even supermodel Cindy Crawford was hired to help promote the car. For its first full model year, a total of 25,411 units were sold and about the same number in 1998. But in 1999, it dropped to around 15,000 examples and by 2001 it was down to only 9,764. Needless to say, Cadillac came to the conclusion it needed to rethink this whole sport sedan thing.

Instead of a second-generation Catera, the first-gen Cadillac CTS was born (which has since been succeeded by the Cadillac CT5). But the Catera still had a great platform that was simply not realized to its full potential. Fortunately, some gearheads were fully aware of what else could be possible. One such group was Lingenfelter Performance Engineering (LPE).

This 2001 Cadillac Catera currently up for sale on Bring A Trailer was sent to Lingenfelter for some serious upgrades, specifically a 5.7-liter LS6 V8. This was later replaced with its current 7.0-liter LS7 V8. LPE built it with a Corvette C5R-based block, ported LS6 heads, an LS6 intake, and even a custom exhaust system. It was then fitted with a Tremec six-speed manual. The modifications didn't stop there. A limited-slip differential, Eibach and Steinmetz suspension components, 17-wheels and touring car-spec disc brakes, and numerous other upgrades followed.

The interior has a cool three-spoke Momo steering wheel, a Bose sound system with a CD changer, and even Cadillac V-Spec badges. The seller has performed all maintenance personally and it was even featured in the October 2002 issue of GM High-Tech Performance magazine, a copy of which is included in the sale.

As of this writing, the highest bid was $5,700 but the auction isn't over until Monday, July 27.