2010 Geneva Auto Show: Lotus Evora 414E Hybrid With Sound Effects
By John O'Dell February 24, 2010
Lotus 414E Hybrid "technology demonstrator" concept's power system and range-extending 3-cylinder engine-generator, viewed through the two-seat sport car's see-though "engine" hatch.
By John O'Dell, Senior Editor
Lotus Engineering already has shown us its extended-range hybrid engine and a fancy sound effects generator that renders audible to pedestrians, bicyclists and other motorists an otherwise quiet electric car or hybrid running in all-electric mode.
Now the company has put them together in a concept car of its own - the Lotus 414E extended-range hybrid, which it will be unveiling at the Geneva Auto Show next month.
The hybrid uses the chassis and body from the conventional Lotus Evora (right), but replaces the drivetrain with a hybid electric system featuring a pair of rear-mounted electric motors - one for each wheel.
They are powered from a rechargeable lithium ion battery pack and a 1.2-liter, three-cylinder flex-fuel engine that's used as a generator to extend the 414E's range once the initial battery charge is depleted.
Think of it as a sports car-sized variation of the system used by General Motors in the Chevrolet Volt.
Lotus claims the lightweight two-seater will travel up to 35 miles on battery power alone before the range extender/generator kicks in.
Monoblock
The battery pack is made of flat lithium polymer cells with 17 kilowatt-hours of storage capacity (Lotus doesn't say how much is usable, but it is typically 50 to 80 percent in this type of set-up - deeper discharge can severely shorten battery life).
The unique aluminum monoblock engine-generator (left), a Lotus design, is rated at 47 horsepower at 3,500 rpm and weighs just under 200 pounds.
The compact design integrates the cylinder block, cylinder head and exhaust manifiold in a single casting, which Lotus says results not only in less mass but in lower emissions and greater durability.
Total range on a full battery and a tank of gas or ethanol (or another of the alcohol fuels) is about 300 miles, when driven sensibly.
Shifty
This being a Lotus, that's probably not in the cards, but 300 miles is the only figure we can get.
Lotus has equipped the hybrid concept with a hands-off Eco mode and a Sport mode that brings into play a 7-speed, steering column-mounted paddle shifter that simulates running through the gears of a conventional dual-clutch transmission.
One particularly neat feature - when downshifting, the shifter engages varying degrees of regenerative braking to mimic the feel of engine-braking with a conventional transmission.
The shifter also electronically simulates the "gear change" jolt of a regular transmission, so it feels as though you are running through all seven gears even though the car actually operates with a single-speed reduction gear.
The 414e sound package also makes it sound as though you're shifting - or idling, cruising or accelerating - and in four different modes.
Sound, Not Silence.
Co-developed with audio specialisrt Harman International - and first shown in August, 2008 - the HALOsonic "noise solutions"ackage on board the 414E solves the problem of silent-running EVs that can present a safety threat to pedestrians, the sight- or hearing- impaired, bicyclists and even other drivers (especially those with a cell phone curtailing their normal hearing and attention-paying abilities).
It provides four driver-selectable sound modes.
----------
Original 2008 demonstration showed how Lotus-harman sound generator warned pedestrians that a hybrid was nearby.
----------
Two of them - called Flat 6 and V12 - emulate conventional internal combustion engines, and two - Futuristic 1 and Futuristic 2 - offer electronic mixes, one a blend of a conventional engine and a turbine whine, the other sounding a bit like a synthesizer's version of a jet engine.
There's aslo a back-up "beep," the same kind of warning tone you hear on dump trucks.
The original version, which you can listen to here, also offered "American V8," but that seems to have been eliminated for the Euro-centric Geneva show.
The sound effects are broadcast inside the cabin through the car's audio system and outside via speakers mounted front and rear.
Performance Claims
The faux engine noises may not be everyone's cup 'o tea - many hybrid and EV drivers like the absence of engine and exhaust tones.
But they are indicative of the 414E's oomph.
This may be a hybrid, but its not a Prius.
The 414 designation comes from the overall powertrain rating of 414 horsepower, as measured by engineers in Germany. That would be 410 horsepower in the U.S.
But the battery pack is rated at maximum output of 100 kilowatts - equal to just 134 horsepower, which is what it feeds to the motors - far less than their 204-horsepower ratings (and yes, 204 x 2 equals 408, not 410 or 414, but what's a few horses between friends?)
In the EV world, ponies aren't as important as torque, anyhow, and each of the 414E's electric motors deivers 295 lb.-ft. of torque to its assigned wheel, Lotus says.
That's sufficient for a 0-60 time of 4.0 seconds no matter which horsepower figure you use. Lotus isn't talking about top speed.
The motor-controlled rear wheels can spin independently - at different speeds and torque levels when needed for traction and to enhance cornering and low-speed handling, especially good when parallel parking. Lotus calls it "torque vectoring."
Lotus calls the whole 414E package a "technology demonstrator," meaning it's packed a lot of stuff on board that it would like to sell to other automakers, or perhaps use in a car to be made at some future date by Lotus' parent, the Malaysian automaker Proton.
We call it a heck of a package that we'd love to see on a retail-ready car like the 2010 Lotus Evora below, instead of on a car show concept.
LEAVE A COMMENT