Looking to invest in a classic car in 2015? The Lamborghini Countach is one to consider.

According to figures from classic car insurer Hargerty, the Italian model has increased in auction value by 175% during 2014.

The Countach's scissor doors were revolutionary in 1974

That makes it the best performing car in Hagerty's classic car index, beating off competition from other esteemed marques including Ferrari and Porsche.

Lamborghini produced just 2,000 Countachs between 1974 and 1990. That makes them rare today.

And, crucially, they're also hugely desirable. With its scissor doors and sleek lines, the Countach was the stuff of dreams for many an adolescent, and featured in bedroom posters across the land.

"People of that age now have a little bit of money and it's cool to have a Countach," McKeel Hagerty, Hagerty's CEO explained to CNBC.

"Not many people have a Countach. It was an amazing looking car, a little bit eccentric mechanically, but a wonderful car."

Countachs are now routinely making close to $750,000, whereas they were changing hands for as little as $200,000 last year.

Sunbeam Tigers have also had a strong year - up 61% in value.

$1.3bn worth of classic cars sold in the US in 2014, according to Hagerty. That's up from $1.2bn in 2013.

Yet these promising figures come amid a slow down for the classic car market.

According to classic car experts HAGI, the market has grown by 15.3% between January and November. Impressive stuff, but still significantly down on the 46.7% gains posted in 2013.

Hagerty predicts the market will increase by just 5% next year - still growth that puts many traditional investments to shame.