If you are referring to the 1/16 scale super detailed funny cars, they were originally part of "Racing Scenes" and sold separately (bodies, chassis, engines, and drivers). There was also a speed shop and mechanics figures all sold separately similar to Monster Scenes and Prehistoric Scenes. They were super detailed kits that were somewhat pricey and didn't sell well. That was in 1974.
In 1975 Aurora discontinued the "Racing Scenes" and sold the two funny cars (Pinto and Vega) as complete kits. They still didn't sell very well and were discontinued in 1976. When Aurora's kit line was sold to Monogram, they were among the molds acquired. As far as I know Monogram never re-issued them and more than likely the molds were scrapped.
By most standards, they were the finest funny car kits ever produced, a pet project of Jim Keeler who, when hired by Aurora, wanted to outdo his former employer, Revell.
Aurora didn't reissue them because Aurora went out of business. The kits arrived rather late in the Aurora cycle and were not on the market long compared to most of Aurora's other, aged, product line. I think they were only on the market 3-4 years out of Aurora's 25 +/- year history. And, back in the day, the kits were not super sellers. I would be curious to know of Revell still owns those molds ?
Monogram scrapped the molds after purchasing them from Aurora. I've read that in several different Aurora history type books. Guess there is the posiibility of them still existing but I doubt it.