Tesla's market cap is nearly the sum of General Motors and Ford.

CNBC's Jim Cramer on Tuesday said he's "dumbfounded" that the electric carmaker isn't even higher, saying it could be double that of the traditional automakers.

"Because the stock market loves growth and this market, in particular, can't get enough of it," the "Mad Money" host said. "Tesla has growth in spades; of course investors will pay up for it. GM has barely any growth. Ford's actually shrinking. Nobody wants to pay up for stagnation."

Tesla on Tuesday opened the doors to its new production facility in China. CEO Elon Musk danced on stage to celebrate the launch of the Model Y factory and investors awarded the company with a nearly 4% gain to the stock price.

The stock closed the session at a new high of $469.06, giving Tesla an $84.5 billion market cap. That compares to GM's $50.2 billion value and Ford's $36.7 billion.

Tesla, founded roughly 100 years after the two Detroit motor companies, is now within $2.5 billion of Ford and GM's combined market caps. Tesla has long faced questions about if it can manage to meet the production capacities of the long-time car companies that once ranked among the leading global corporations.

"Wake me up when Tesla's double the value of Ford and GM put together," Cramer said. "That's when I might take [a] pause in my bullishness, but only if GM and Ford gain in value from here, because if they decline a double's too easy."

Now Tesla, Cramer said, has what GM and Ford want. Electric vehicles are the future, a future that GM and Ford have not been able to penetrate. Additionally, Tesla's business is growing in China. Meanwhile, GM saw a double-digit sales decline in the country and Ford is expected to post a similar showing.

Once harsh critic of Tesla, Cramer has given a bullish outlook on the stock after the company put a series of negative headlines involving Musk behind them. Other critics and short-sellers – investors who bet against a stock – are buoying the stock to new heights as they convert from bears to bulls, the host noted.

Tesla shocked Wall Street in October when it turned a profit of $1.86 per share when analysts estimated the company would lose 29 cents per share, according to FactSet. Analysts are forecasting a profit of $1.53 per share when Tesla reports fourth-quarter earnings potentially next month.

Tesla said it delivered a record 112,000 cars in the fourth quarter, topping expectations. The company has reported about 367,500 global sales in 2019, which is up 50% from the year prior.

"I got really bullish on Tesla about 150 points ago when it became clear that the company can make money — maybe even a lot of money — as soon as next year," Cramer said.