Wealthy car collectors shelled out more than $400 million for collectible cars at the Pebble Beach auctions over the weekend, shattering the previous record and raising new questions about a vintage-car bubble.
According to Hagerty, the collectible car insurance firm, the sales totals for auctions at Gooding & Co., RM Auctions, Mecum Auctions and others hit $399 million by late Sunday, when the official event wrapped up.
When all the deals are done, including side deals that are not officially tied to the auctions, the total will surpass $400 million, Hagerty said. That tops last year's record total of $312 million.
Read MoreMost expensive car ever auctioned
The average sale price jumped nearly 30 percent, to $535,648 from $416,696, suggesting that the quality of this year's offerings was higher along with prices.
A 1962 Ferrari GTO became the most expensive car ever sold at auction, fetching $38 million including auction fees.
Although the overall sales total from the auction was slightly less than the $450 million to $500 million that some expected, it was still a big jump.
"There was a great deal of hype heading into the Monterey auctions," said McKeel Hagerty, CEO of Hagerty. "On the surface it was a record year and several individual record sales were set—including the highest price ever paid for a car at public auction. However, the overall results indicate that rationality overcame much of the hype."
The prices and totals show that the spending spree in collectible cars continues to rage on, as newly rich collectors from around the world chase a small number of top, vintage cars.
Wealthy collectors say there simply are very few places to put their excess wealth these days. With interest rates low and stocks increasingly volatile, rich car lovers would rather invest in something that can hold its value—and they can drive and enjoy.
"You buy what you like and if it goes down in value, at least you like it," said Jay Leno, the comedian and car collector who was at Pebble Beach. "So you have something you enjoy."
Read MoreCars to watch at Pebble Beach
Ferraris have become far and away the favorite car of rich collectors, accounting for nine of the top 10 sellers by price. Yet Porsche and Mercedes models have also surged in value, with sales prices for the Mercedes 300 SL Gullwing doubling over the past two years to $1.6 million.
Some market watchers say such rapid price increases are unsustainable and that the market is due for a correction.
"The market is out of control," said Winston Goodfellow, a collectible car expert and author of The Goodfellow Perspective blog. "Things are going up 50 percent in six months. That's not normal market behavior."
Goodfellow said that his analysis of prices for specific models over time, akin to a price-earnings ratio for stocks, shows a market poised for a fall.
Read MoreExperts say $63M Ferrari is a fake
"The dashboard warning lights are flashing and no one is paying attention," he said. "I think we'll have a correction, maybe not a crash. For me a correction is healthy."
Until then, however, collectible car prices are getting fast and furious, especially for Ferraris.
Here are the top 10 sellers by price over the weekend, according to Hagerty.
1. 1962 Ferrari 250 GTO Coupe, $38,115,000 (Bonhams)
2. 1964 Ferrari 275 GTB/C Speciale Coupe, $26,400,000 (RM Auctions)
3. 1961 Ferrari 250 GT California SWB Spyder (closed headlight), $15,180,000 (Gooding)
4. 1964 Ferrari 250 LM Coupe, $11,550,000 (RM Auctions)
5. 1967 Ferrari 275 GTB/4 Coupe, $10,175,000 (RM Auctions)
6. 1953 Ferrari 250 MM Coupe, $7,260,000 (Bonhams)
7. 1965 Ford GT40 Prototype Roadster, $6,930,000 (RM Auctions)
8. 1962 Ferrari 250 GT SWB Speciale Aerodinamica Coupe, $6,875,000 (Bonhams)
9. 1958 Ferrari 250 SI Cabriolet (closed headlight), $6,820,000 (Bonhams)
10.1959 Ferrari 250 SI Cabriolet (open headlight), $5,610,000 (Gooding)
—By CNBC's Robert Frank