Grand Design
A bold attempt at a new normal… and a precursor to today’s hybrids
Under the skin of Honda’s Insight
With legislation already announced to draw to a close the production of conventional fossil-fuelled vehicles in just a decade, we might recall the serious efforts being made two decades ago to reimagine the cars of the future. Honda’s Insight wasn’t all-electric. That was a step too far at the time, but the Insight was certainly radical, tested in the marketplace fully for seven years and now available, from time to time, as a ‘modern classic’.
Toyota’s contemporary was the Prius that had a two-year head start, but was seven months after the Honda onto the US market. The Insight’s compact footprint, sci-fi streamlining and integrated petrolelectric power plant were enough of a surprise, without the combination of just two seats and an optimistically high price.
The mission, at this stage, was a stepchange in fuel economy and emissions, rather than today’s abandonment of internal combustion technology altogether, and it was hoped to combine as much advanced thinking as possible without limiting the car’s appeal. The arithmetic didn’t add up, though, for the mainstream customer and nor did the overall package, neither family car nor sportster.
Sales were sluggish, and many cars remained unsold, as demonstrators.
BATTERIES
The J-VX prototype’s ‘ultracapacitor’ storage was replaced for the production Insight by 120 x 1.2v NIMH batteries, connected to deliver 144v DC and
6.5 AH. Periodic battery charge/discharge cycling helps to keep the hybrid battery cells balanced and prolongs their life.
LIGHTWEIGHT ENGINE
The naturally aspirated 1.0 litre
3-cylinder 12-valve
VTEC-E lean-burn electronically injected petrol engine has a timing chain rather than nowubiquitous belt, is cast from aluminium, has a magnesium alloy sump and plastic ancillaries to minimise weight like every other element of the car’s design. Even the engine oil is low viscosity synthetic 0W-20 for low resistance and enhanced fuel economy. Iridium-tipped spark plugs have a long life and there are individual coil packs for each cylinder.
FRONT SUSPENSION
Front independent Macpherson struts have lightweight hollow damper rods. The lower suspension arms are forged aluminium, as is the steering knuckle. The lower arms attach to a forged aluminium mount and to a portal-shaped 0.66in diameter anti-roll bar. It’s a compact and neat solution, designed to maintain virtually constant toe-in and camber in compression, for optimal handling, comfort and low rolling resistance.
‘IMA’
Honda’s parallel hybrid ‘integrated motor assist’ front-wheel-drive driveline consists of an ultra-thin 2.3in permanent magnet electric motor ‘slice’ sandwiched between a light compact petrol engine and 5-speed manual or CVT transmission that assists with acceleration and helps slow the car with regenerative braking. The electric motor also acts as starter, alternator and engine balancer. Unlike a Prius, the Insight cannot run electric-only.
EFFICIENT TRANSMISSION
The 5-speed gearbox, like the rest of the car’s construction, was a clean sheet design focused on weight saving, compactness and economy, and only weighs 41kg. Its efficient lubrication system requires less oil and a smaller sump, while the mass of the internals is kept low to reduce inertia and energy loss.
STEERING
A high-mounted electric power assisted rack & pinion, with zero front toe-in for low rolling resistance, somewhat compromises feel and directional stability, but as little as ⅛in significantly impacts fuel economy. The system is less power hungry, more compact and lighter than conventional hydraulic assistance. The padded three-spoke steering wheel is as used on the Honda S2000 sports car, with 3.2 turns lock-to-lock.
BRAKES
Front power-assisted 9.1in ventilated discs and rear 7.1in finned drums, with ABS and emergency brake assist, have a relatively easy life with the Insight’s regenerative braking being the first response to the pedal. Calipers and drums are aluminium to minimise unsprung and overall weight.
THE DRIVE
The Insight, despite its modest power, is still fun, nimble and with a surprising top speed.
Its light weight, and peerless streamlining that includes a flat featureless underside, make it a lot more entertaining than the contemporary first-generation Prius. Electric power steering is standard,the ride is uncannily quiet, the brakes grippy and sharp and the air-conditioning, optional in the first year and then standard, a welcome surprise.
STRUCTURE
An advanced combination of cast, extruded and pressed aluminium is light, very stiff and easily recycled, and keeps the weight below 800kg. Insights were built in the same Suzuka factory as Honda’s aluminium-bodied NSX sports car.
REAR SUSPENSION WHEELS & TYRES
Narrow low-resistance Bridgestone Potenza 165/65SR-14 tyres, with high recommended front/ rear pressures of 38/35 psi, reduce rolling resistance by 40% and are 5% lighter, but deliver limited directional stability in cross-winds and on poor or wet road surfaces. The 14 x 5.5J road wheels and spacesaver spare are lightweight alloy.
Coil-sprung steel trailing arms with forward leaning dampers are attached about a third of the way back from substantial rubber-bushed pivot points to an upward curved steel ‘twist-beam’ that braces the compact assembly and also functions as an anti-roll bar. The whole arrangement is very compact, and makes room for a space-saver spare wheel and 10 gallon fuel tank under the flat-floored luggage area.
ACCOMMODATION
It’s a small car, and you have to more or less ‘slide’ in and drop yourself in the very low, lightweight seat, but once in, those bolstered seats are quite comfortable. An Achilles heel of the Insight was that, while not a sports car, it still only had two seats. Its J-VX coupé predecessor prototype had very limited luggage space, but did have rear seats that would be sacrificed for production in favour of battery accommodation and 5 ft3 of luggage space. The interior environment is modern and stylish, and incorporates driver map lights and passenger front airbags.