"""As you know, here at Autopia, we’re big fans of the engine swaps. And the more high tech or the crazier, the better. We’re not sure if this is either the techiest or the nuttiest, but some really well-meaning folks decided to take a 3-cylinder Volkswagen TDi mill and drop it into an first–gen Honda Insight and still use the hybrid drivetrain. And the mileage numbers are very impressive.

Putting a new Mercedes diesel into an old chassis, a Power-Stroke Ford into a Checker Marathon or a even giving a first-generation Rabbit a serious upgrade, we’ve always been interested in cool engine swaps. But doing an engine swap in an Insight and keeping the hybrid drive train just about pegged our nerd-meter.

Honda’s first Insight was the first hybrid car sold in North America. Greenies were all over the thing, and to be sure it was, and even by today’s standards, still is a technological marvel. But any technology could be improved, even something as groundbreaking as the Insight.

Or at least that’s what the folks at Red Light Racing started to ponder. So if you could improve the Insight, what would you do? Well, the most obvious answer is take out the gasoline-burning engine and drop in a more efficient diesel. For some reason, the Red Light folks thought that the best oil-burning mill to drop in would be Volkswagen’s TDi 3-cylinder from the Euro-only Lupo.

This is a lot more complicated than swapping out a Civic motor for a new Integra mill.

First on Red Light Racing’s to-do list was dump the old 1.0-liter, 70-hp gasoline engine and replace it with an oil-burning 1.2-liter PD TDi from a Volkswagen Lupo. Next on the list is to hook the TDi up to the hybrid drivetrain. Before they did that, they ran the Insight 1G on just the VW engine. Bottom line: 80 mpg, which is up considerably from the original’s 53 mpg. When then hybrid portion of things is hooked up and fully sorted, they are expecting further gains of around 15 to 20 percent.

Just as easy as changing a light bulb? Far from it. Red Light Racing had to chase down issues from bracketry to emissions systems to ECU problems. The last time we saw someone hassling with a car this much, it was made by British Leyland in the mid-’70s.

In a recent interview with AutoblogGreen, Red Light Racing’s lead engineer Jake Staub said, “The main idea was to take existing hardware, hack it, and make a vehicle that could be produced by major manufacturers or individuals that would deliver tremendous fuel economy without a tremendous leap in technology. I believe we succeeded.”

Someone from a major manufacturer should hire every one of these people."""---AUTOPIA