VinFast soared in its debut as a public company, vaulting its market capitalization beyond that of General Motors and Ford Motor, as traders flipped shares of the electric-vehicle maker.

The Vietnamese company, which went public in a SPAC deal, is worth about $85 billion after shares soared Tuesday, rising to $37.06 in New York — up more than 270 percent from the SPAC’s IPO price and more than tripling the deal’s $23 billion implied equity value.

VinFast debuted on the Nasdaq Global Select Market under the symbol VFS to a flurry of trading and volatility halts after completing a merger with special-purpose acquisition company Black Spade Acquisition.

The share surge from the closing price of the SPAC on Monday makes the company the top performing de-SPAC to debut this year on a U.S. exchange.

The massive valuation makes VinFast worth more than BMW, and more than Ford and Rivian combined on paper in terms of market capitalization but lagging BYD’s market value.

However, VinFast is a low-float company. There are a small number of shares available for trading — just 1.3 million shares of the SPAC remain after redemptions — which means the stock’s move and value are prone to large swings.

Regulatory filings show Pham Nhat Vuong, Vietnam’s wealthiest man and VinFast’s founder, controls about 99 percent of the entity, partly via shares held by his wife and Vingroup JSC.

That means the vast majority of shares are locked up and unavailable to investors who would have gained from Tuesday’s rally.

Additionally, companies that merge with black check firms tend to experience rallies that fizzle out a few trading sessions after a deal closes, when social media buzz subsides.

De-SPACs that have made their debut this year have seen a median slump of about 45 percent, with 18 of them wiping out more than 70 percent of their value, according to data compiled by Bloomberg.