Extending the rebound in motorsports spending, North American-based companies will spend an estimated $3.76 billion to sponsor motorsports teams, tracks and sanctioning bodies in 2013, up 3.9 percent from 2012.

While sponsorship spending has come a long way since the dark days of 2008-2009, not all is rosy on the motorsports front.

Pressured by high price tags, lackluster TV ratings and a longer decision-making process, the projection lags IEG SR’s 5.5 percent increase in overall sponsorship spending and 6 percent growth for all sports properties.

Nowhere is sluggish spending more evident than NASCAR, where corporate cutbacks have left a number of teams scrambling for sponsors. That includes several high-profile teams, with Dale Earnhardt Jr. and other drivers still trying to patch together deals that will carry them through the season.

Earnhardt—NASCAR’s most popular driver—reportedly lacks a title sponsor for roughly one-third of races this year.

One major challenge: finding companies willing to commit to an entire season. Continuing a trend seen over the past five years, many companies have replaced full-season sponsorships with partial-season deals that offer exposure in select markets.

Among notable new deals, Textron Inc. earlier this year announced a multirace agreement with Chip Ganassi Racing Teams. The deal includes teams in the NASCAR Sprint Cup Series, IZOD IndyCar Series and the Grand-Am Rolex Sports Car Series.

Textron will use the partnership to promote three brands: Cessna Aircraft Co., Bell Helicopter and E-Z-GO golf carts.

At the sanctioning body level, Featherlite Trailers extended its decades-long NASCAR partnership through 2018.

On the IndyCar front, electronic cigarette maker blu eCigs will title the No. 17 Rahal Letterman Lanigan Racing team at the April 19-21 Toyota Grand Prix of Long Beach. The brand will serve as an associate sponsor of the team’s No. 15 car driven by Graham Rahal for the entire 2013 season.