It has been over 20 years but once you see it you’ll never forget it. We’re speaking about the Mosler twin-engine Eldorado. And this was not a one-off. These were made to order and five of them got built before clearer heads prevailed. So you could buy your own twin-engine Cadillac in 2000 from Mosler. 

Cadillac was known for its V-16 engines in the 1930s

You have to understand that Cadillac was known for its V-16 engines in the 1930s. These were magnificent cars and still the most collectible Cadillacs ever. The car’s designer Warren Mosler wanted to see Cadillac return to those days but with a modern take. If the name sounds familiar it should. Mosler designed and then built those Consulier GTP race cars in the 1980s. IMSA eventually banned them because nothing else could beat them. 

The twin-engine Eldo came to fruition after Mosler entertained making an Eldo mid-engine. With the well-engineered Northstar V8 all packaged together with front-wheel-drive, he could move the unit back a few feet and get an instant mid-engine Eldorado. Theoretically, that is what Mosler started to do. But then the plan changed.

A second Northstar engine was engineered into the back seat

Supposedly, a golf buddy suggested if a mid-engine was that cool then a twin-engine would be over the top. And it would harken back to Cadillac’s V16 glory days. Plus, Mosler wouldn’t have to do anything to the front engine. He’d only need to engineer a second Northstar engine into the back seat. And that’s what he did. The “TwinStar” was born.

To accomplish the transformation without having to radically alter the length of a stock Eldorado the rear wheel openings were moved rearward. That radically changed the look of the car. But the awkward styling draws like ants to a picnic. That added landscape between the doors and wheel openings saw a large scoop added. The scoops were meant to bring outside air to the rear engine. So add two radiators to the redundancy list. 

The output by the front engine was less than that of the rear

There were problems from the start. The middle engine was not the same Northstar as the one that came in the Eldorado stock. In front was the 275 hp engine, but for the middle Mosler chose the optional 300 hp Northstar. So the output by the front engine was less than that of the rear. 

Another problem was that each engine ran separately without any shared computer information. Only the throttle linkage was common. With different power each engine caused its own transmission to shift at different times. But there’s more.

The mid-engine pushed the car with more power than the front

Each engine computer was also independent. Unfortunately, with the mid-engine sometimes pushing the car with more power it would cause the front engine to play catchup. This would cause it to hit the rev limiter for the front engine until the computer got overwhelmed. At that point, it would put the front engine into limp mode.

As there were two radiators and ECUs so too were two gauge clusters, ignition switches, and virtually every other component that one engine needed. When the TwinStar was running on both engines, which it didn’t always do, fuel consumption was also doubled. On average the Eldo could hit 10 mpg. 

The TwinStar’s handling was said to be quite good

Specifications listed 575 hp combined. Zero to 60 times were 5.0 seconds with quarter-mile elapsed times in 13.4 seconds. That makes it almost 2.5 seconds quicker than a stock Eldorado. Handling was said to be quite good according to Car and Driver that did a contemporary test of the TwinStar. 

With the second engine installed the TwinStar sold for around $70,000 which in 2021 dollars is over $106,000. The late Clarence Clemmons from Bruce Springsteen’s E-Street Band was an owner. According to Hagerty Insurance, prices average around $40,000 on the rare occasion a TwinStar pops up for sale. We can’t think of more fun than an odd-looking old Cadillac with twin engines as a daily driver.