Chris Woodyard

USA TODAY

A 1970 Pontiac Firebird rebuilt to modern-car standards and hopped up to an astounding 1,200 horsepower sold at auction Saturday. It went for $87,000, far behind some other cars at the Mecum Chicago Auction.

The 1970 Firebird had been rebuilt with modern components. The 480-cubic-inch Pontiac engine has been rebored for brute power, helped along by twin turbochargers. Altogether, the car spits out 1,200 horsepower, equal to a Bugatti Veyron, according to its owner.

The price seemed like a bargain compared to the other American sports and muscle cars on the block. At midday, the top price-fetchers were a pair of nearly decade-old Ford GTs, both with less than 400 miles on the odometer, that went for $335,000 and $300,000 respectively.

The Pontiac, however, is playing in the hot part of the auction market right now.

As Gen X'ers hit their 40s and have some money to invest in classic cars, many are opting for muscle cars restored with modern parts, so-called "restomods," says Rick Drewry, senior specialist for collector cars for American Modern, an insurer of collector cars.

"Boomers are starting to exit and Gen X'ers are coming in," he says.

Gen X likes classic American muscle cars all the way through the '90s. They just don't care if the car are completely authentic, which was of more concern to Boomers.

In another big auction this weekend, RM Auctions says it saw record sales at its annual auction in Hershey, Pa. Some 157 vehicles sold for more than $14 million.

Tops was a 1930 Cadillac V-16 Roadster that went for $1.1 million. The car had been in the same family's collection since 1933.