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1958 Cadillac Eldorado Biarritz ‘Raindrop’ Prototype

1958 Cadillac Eldorado Biarritz ‘Raindrop’ Prototype

1958 Cadillac Eldorado Biarritz ‘Raindrop’ Prototype

This Eldorado Biarritz might look standard, but it’s one a few ‘dream cars’ that were built up the the Motorama shows. This is the first GM that featrued an automatically raising convertible top. In the advent of rain it would deploy the top automatically. The sole ‘Raindrop’ Biarritz was sold at RM Auctions 2010 Automobiles of Arizona sale for $220,000 with an estimate of $250,000-$300,000 USD.

Auction Description Excerpt

During the 1958 model year, a total of 815 Biarritz convertibles were produced, and from that number, five were taken off the line and sent to Cadillac’s Design Studios where they received special treatment to make them the show cars for Cadillac in 1958. This is one of the five cars, equipped with the “Raindrop” feature. Mounted on the rear panel between the deck lid and the convertible boot well was a sensor that, upon detecting the slightest amount of water, would set into motion an automatic system designed to raise the car’s convertible top, thereby protecting its interior while the owner could continue enjoying a round of golf, leisurely luncheon date or shopping expedition.

According to the promotional material of the day, the top was reworked so that when retracted into the down position all of its components were below the beltline of the car. A custom-built three piece cover replaced the original parade boot and allowed for automatic operation of the top. When the sensor, officially called the Humidity Control, was hit by a single drop of rain, it would set in motion a mechanical symphony. Starting with the back panel, a center section would slide out of the way while the side panels lifted and opened up. Next, the top would lift up and out of its storage space and fold out to its open position, automatically locking itself to the windshield pillar. Once the top was firmly in place, the front door windows would raise automatically, followed by the rear quarter glass. All of this took place in less than a minute and changed the car from an open-air luxury cruiser to a snug and dry comfortable enclosed coupe.

Having started life as a regular production unit, it was a fully functional car and was driven on a regular basis during its official tour of duty, which included a visit to the Michigan State Fair, where one Gerald Beaudoin of Windsor, Ontario first saw it. However, upon its retirement from the show circuit, as so often happens, the decision was made by G.M. executives that this Biarritz with the prototype Raindrop feature would have to be scrapped. The car was therefore sent to a junkyard in Detroit. The engine and transmission were removed and the body was taken off the chassis and cut into two pieces.

According to literature provided by the vendor, Mr. Beaudoin was a Cadillac dealership owner and visited a junkyard in February 1962, four years after the show at the fairgrounds in Michigan. He was in search of a motor, but as he perused the “tele-type,” which listed all parts in the junkyards nearby, he came across a 1958 Eldorado motor equipped with air conditioning. He was convinced this must be the motor from the Raindrop car he saw four years earlier. Upon arriving at the neighboring junkyard, he immediately purchased the S.K. Model motor, along with the remaining parts from four different junkyards. He took all the parts he accumulated, including the original body, triple-carbureted engine, transmission and interior components and returned to Windsor, conducting a two-year restoration and putting everything back together. G.M. reportedly caught wind of his endeavor and pressured him to return the car, resulting in inquiries from customs officers and even the R.C.M.P.

After owning the car for about 20 years and amassing about 30 trophies at car shows, Mr. Beaudoin sold the car to another Canadian, from whom it was acquired by the vendor about 19 years ago. The car has since been recently repainted and has only been driven to local car shows by the owner. As presented, the odometer shows about 8,700 miles, which the owner believes to be original and would have been amassed in its limited car show duties over the years. The vendor also has assorted documentation of the car, including newspaper clippings, pre-restoration photographs from the 1960s as well as build sheets, and a research and development tag.

Story by Supercars, RM Auctions.

In Detail

type Concept / Prototype Car
engine V8
valvetrain OHV
fuel feed 3 2-Barrel Carburetors
power 249.8 kw / 335 bhp
body / frame Steel Body
driven wheels RWD
front brakes Hydraulic Drums
rear brakes Hydraulic Drums
f suspension Independent w/Coil Springs
r suspension Live Axle w/Leaf Springs
wheelbase 3289.3 mm / 129.5 in
transmission Hydramatic Four Speed Automatic