Time Inc. is revving up its video production.

In a bid to boost its video capabilities and sell more sponsored content, the country’s biggest magazine publisher has purchased two automotive-focused YouTube channels, /Drive and Fast Lane Daily. Financial terms weren’t disclosed.

Fast Lane Daily, which features car reviews and test drives, has 300,000 subscribers on YouTube, while /Drive, which takes viewers behind the scenes with videos on road trips, races and the manufacturing of cars, has 1.6 million subscribers.

The deals reflect Time Inc.’s growing bet on car fans and the lucrative marketing dollars spent on targeting them. Earlier this month, the publisher realigned its advertising sales staff, creating specific teams that will focus on automotive, pharmaceuticals and technology/telecommunications. The publisher tapped Mark Ellis as president and chief operating officer of sales and marketing, also overseeing the new automotive sales team.

“There’s an incredible appetite on the behalf of consumers and advertisers for video, and these purchases will enable us to produce more video content and offer marketers more opportunities to distribute native video,” said Edouard Portelette, vice president of business operations for The Foundry.

The purchases are Time Inc.’s latest digital investments, as the company tries to return to revenue growth. Last week, the company disclosed that it had agreed to buy data-driven marketing firm Viant Technology Inc., whose assets include several digital ad technology and media companies including MySpace and Vindico.

During a recent earnings call with investors and analysts, Time Inc. Chief Executive Joe Ripp said the publisher has increased its bet on video, noting that Time Inc. produced 23,000 videos in 2015, up from 8,000 in 2014.

“The TV ecosystem has broken wide open, and we are already participating in this disruption, as advertisers shift dollars into digital video and OTT offerings,” he said.

Time Inc.’s advertising revenue fell 7% in 2105, dragged down by a 10% decline in print and other adverting revenue to $1.32 billion. Digital advertising revenue increased 11% to $331 million, but it wasn’t enough to offset the drop in print.

The company’s investment in the two YouTube channels comes as automotive dealer associations, local auto dealers, and car manufacturers have sharply reduced their print ad spending in auto magazines, while shifting some marketing dollars online. Altogether the trio spent $431 million through the first nine months of 2015 on auto magazine print ads, down from $846 million in 2012, according to Kantar Media.

Both YouTube channels will report to The Foundry, which Time Inc. launched last year to hold its in-house native content and marketing teams. The Foundry also oversees the creation of original consumer content such as the TheDrive.com, an automotive website that launched last fall. On Tuesday, TheDrive.com featured such stories as “Richard Petty’s Greatest Moments, According to Richard Petty.”

It is expected that the production teams associated with Fast Lane Daily, /Drive and TheDrive.com will consolidated into one unit that will produce videos for all three sites.

“We’re going to increase the resources to both of these channels,” added Matt Bean, editorial director for The Foundry. “We can get these guys running at their full potential. This will enable their storytelling abilities to be realized.”

Fast Lane Daily was owned by Emil Rensing, a veteran digital executive, while /Drive was majority owned by video production company TangentVector Inc., based in New York. Mr. Rensing was also an investor in /Drive.

Write to Jeffrey A. Trachtenberg at jeffrey.trachtenberg@wsj.com