Now That’s a Hybrid!

You never know what you’ll find lying around behind your workplace. If you’re NASA Great Lakes driver Claude Lawrence, and you work for Honda, you might find your next racecar.

A suspension development engineer for Honda Development and Manufacturing of America, and a member of Honda of America Racing Team in Ohio, Lawrence noticed  a Honda Insight languishing in the back lot at the office, so he started asking about it. Turns out that Honda had bought the car back to research how well it had held up in the field. After the company was done with testing, the Insight was parked, and it likely was destined to be scrapped. Lawrence had other plans.

“I owned one personally as just my daily commuter, and so it was on my radar that the car was really light and aerodynamic, and I knew people had been K-swapping them,” Lawrence said. “I noticed it had been sitting in the same parking spot for a couple of months, and I started poking around to find out who was responsible for it, and what the plan was. Basically just before we were going to crush it, I was able to get it transferred over to the race team so that we could at least put sticky tires on it and see if it actually had any potential from a handling perspective before we went down the rabbit hole of swapping the engine.”

To refresh your memory, in stock form, the Honda Insight came from the factory with a 1.0-liter three-cylinder and either a five-speed manual or a CVT. The Insight and its successor, the CRZ are two of the few hybrids to have been offered with a manual transmission. The cars were developed in the wind tunnel for maximum fuel economy and the unibody was made entirely of aluminum to minimize weight. They were light to begin with, but with Lawrence’s K swap and all the batteries and hybrid flotsam and jetsam removed, this one weighed just under 1,900 pounds with a driver when he was driving in HPDE3 at PittRace in the summer of 2021.

Honda of America Racing Team was just the team to put on the job of turning a Honda Insight into a car that can turn fast laps on a road course. Most of the K-swaps had been done for drag racing and for street cars where emissions laws don’t prohibit that kind of thing.

“There’s a whole Facebook community of different guys. Typically, they do them as a street car or a drag car. They’re a really, really competent drag car for obvious reasons,” Lawrence said. “You can get a decent amount of power out of the K swap and, you know, it’s super light and super aerodynamic.”

Getting a Honda K20 into the car wasn’t so difficult. Hasport makes mounts that allow for the swap. Because this car was destined for road racing, HART was tasked with getting the car to handle well. They are still on that mission, but we have every confidence they will get the car dialed in.

One of the first suspension modifications involved installing steering knuckles, modified front axles and struts from an Acura RSX. That allowed for the use of larger wheel bearings and larger brakes to arrest the speeds normally seen on road courses. Naturally, Honda Development and Manufacturing of America had plenty of parts for Lawrence to use.

Lawrence designed custom top mounts to adapt the RSX springs to bolt to the Insight body, and made a proprietary bracket to mount the Accord six-speed shifter to the floor. They made the parts in house at Honda Development and Manufacturing of America’s Auto Development Center.

Upon initial modification and testing, the car was sprung far too stiffly. Luckily, the Honda engineering department has the equipment to help sort it out. HART used the suspension parameter measurement machine, which measures wheel rate, how the car rolls and the way alignment changes through wheel stroke. They compiled the data from the machine with driver feedback from the track and skidpad to get a setup that worked up front.

“We actually were able to put the car on there with the RSX springs and compare it against some of our previous race cars that we’ve put on that same machine to try to come up with what the proper spring rate should be for the car’s weight,” Lawrence said. “And that’s how we arrived with the Eibach spring that we ended up choosing.”

They still have some bugs to work out, particularly in the rear, which uses stock springs and a twist-beam axle — not exactly racing technology. It’s still a little under-sprung in the rear and exhibits some strange handling characteristics. The car doesn’t seem to want to take a set, and it seems to squirm a bit in some of the higher-speed corners.

Lawrence said they plan to shorten the rear springs and soften the material used for the rear bump stops. It’s a challenge because the car doesn’t have a rear sway bar and the front bar had to come out to make room for the K20 engine, although an aftermarket header will allow the bar to be reinstalled.

The car is fitted with a full roll cage, but because of the fully aluminum chassis, the mounting plates inside for the main hoop and other bracing structures in effect sandwich the chassis between another plate on the underside. For design parameters, they again turned to Hasport, which still has the Honda Insight that crashed in rather spectacular fashion at El Mirage dry lake bed in 2013, in which the driver escaped with minor injuries.

Currently, Lawrence and HART are using what has become a hybrid of a completely different kind for TREC races. With the 160 horsepower K20 engine, the thing is a hoot to drive. As you might imagine, the team learned during TREC races that the car was still remarkably fuel efficient, which is always a bonus in endurance racing.

“The big thing was, it was using fuel a lot less than we thought it was going to,” Lawrence said, adding that they are also going to use it for driver training for HART. “It really seems like once we get the suspension dialed in, from an endurance car perspective, it should be a pretty competent car.”