Madman Michigander builds go-kart-powered Honda Insight
When Honda introduced the hybrid Insight at the turn of the millennium, it was an answer to a call for cleaner, more fuel-efficient vehicles. Despite its outwardly modest appearance, however, the Insight was very advanced. It represented a kind of brute force approach to tech, a culmination of several R&D tangents Honda had been on, combining lessons learned from its lean-burning flyweight hatchbacks of yore with cutting-edge aerodynamic tricks and electrified drivetrains. Recognizing these accomplishments twenty some-odd years later, a sarcastic Michigander is doing much a much stranger sort of engineering blitz with his Insight, stuffing a Harbor Freight go-kart engine under the hybrid’s aluminum hood—just for kicks.
“It almost looks like a factory install. And given Hondas are mostly made from lawnmower parts anyways, I reckon that’s pretty accurate,” says the cheeky, intrepid mad scientist. He maintains that hot-rodding one of Harbor Freight’s beloved discount engines is simply more interesting in an Insight, and I’ll agree with him there. It’s genuinely more exciting and less predictable to follow along than it would be with some generic go-kart, watching how the bizarre Honda responds to each performance tweak.
For the Insight project, Fujioko built a subframe off the Honda’s bellhousing, retaining the original five-speed gearbox but replacing the original 1.0-liter ECA1 three-banger for a $99 single-cylinder, .212-liter (212cc) Predator engine. To connect power, a go-kart CVT transmission moves a chain drive that provides an additional gear reduction before spinning the five-speed’s input shaft through a modified clutch disc. There’s no actual clutch; instead, the hub of the disc functions as an adapter for the input shaft to the homebrew powertrain ahead of it.
The CVT serves two important purposes. It acts as a clutch when the vehicle is stopped and actively shifting, and it multiplies the torque of the little Predator engine over a wider rev range. To drive the Insight, the driver selects first gear and then applies throttle. Once the go-kart CVT spins up and begins to transmit power, the driver rides it out until the engine reaches the end of the CVT’s gear ratios, releases the throttle to grab the next gear, and then winds the Predator back up against the CVT’s range of ratios.
As you can imagine, the quest to find out just how fast you can make a Honda go with “lawn mower” engines is one built upon patience. Acceleration with such a powertrain is best defined as “possible,” and the 54-mph top speed is modest, so the latest phase of this project has involved upgrading to Harbor Freight’s big-boy single-cylinder: the hemi-headed 420cc big-block.
Dig into this series and let us know what you think—what car would you swap with Lawn Power given a budget of a couple Benjamins and an afternoon or two behind a welding mask?