Nov 3, 2003 at 12:00
It's not just Lee Goldberg who can go green for a while! This Editor was fortunate to enjoy an extended test drive of a 2004 Honda Civic Hybrid recently, and I found the experience both exciting and a little unnerving.
Readers of green-techZONE probably don't need to be told much about how this vehicle operates, but as a reminder it has a 1339 cc aluminum alloy block and head in-line 4-cylinder gas engine, with a permanent magnet dc electric motor coupled on the engine drive. The electric motor is powered by a 144-V battery made up of 120 1.2-V Ni-MH cells which are stacked behind the rear passenger seats. The space is stolen from the trunk capacity -- rather than the rear seat legroom, which is already too short for most adults -- reducing the trunk capacity from 12.9 cubic feet to 10.1 cubic feet but it's probably still space enough for the majority of a family's grocery shopping. Honda calls it Integrated Motor Assist (IMA) and it's difficult to understand exactly how much power is actually added to the drivetrain because the company doesn't use apples-to-apples numbers in its power and torque, even between their automatic (continuous cone variation) and 5-speed manual versions of the vehicle. Suffice it to say the IMA provides 13.4 hp at 4000 rpm but only adds 8 hp to the combined engine/IMA output at 5700 rpm to take it from 85 hp to 93 hp.
On the road, however, the biggest improvement with IMA assist is in the low rev torque: Adding the IMA to the engine increases torque from 87 lb.-ft (at 3300 rpm) to 105 lb.-ft (at 3000 rpm) in the automatic, and up to 116 lb.-ft (at 1550 rpm) in the manual. I took the car, which was an automatic, up a 25% grade hill and it handled it with no problem whatever. Going down the same hill the regenerative engine braking (as the electric motor now becomes full-time generator) is massive compared with just the small gas engine. The same is true with normal acceleration in town: It is as good as any small car I have driven and is so much quieter… And presumably the extra torque in the manual transmission version makes it even better at low speeds.
But if you think that is quiet it is eerie when you pull to a halt and the engine stops! Providing the air conditioning/heat system is switched into the economy mode the gas engine will simply turn off indicated by an "Auto Stop" LED just below "0" on the tachometer. Remove your foot from the brake and the IMA starts to rotate the engine again and you're off. There are a couple of interesting problems there: If you take your foot off the brake and then re-apply your foot the engine doesn't stop again (software glitch?) Also, the tickover speed is so low (200 rpm or so, but the tachometer is vaguely calibrated below 1000 rpm) that a hill start is hazardous in the automatic if you're not expecting a vehicle to roll backwards at drive off. There is also a small hiccup when the IMA-rotated engine also becomes a gas engine again, although many drivers probably wouldn't notice the effect.
In town driving is one thing: Once on the highway the mid-speed acceleration is rather lacking and -- in the automatic version at least -- the engine has to be worked really hard to get the car into any kind of safe overtaking role. For somebody who has been used to 8 years of driving supercharged V-6s, that would require a lot of additional faith on the main coastal US-101 highway, where I know every possible spot for overtaking lumbering RVs.
The Hybrid is well equipped -- to at least to Civic LX sedan standards -- and is rather different from the rather utilitarian Toyota Prius I once sat in. I had plenty of driver legroom and more headroom than in my existing vehicle - it was a very satisfactory two-seater but not, in my opinion, a real five-seater vehicle. Turning diameter is also nice at 34.8 feet and, surprisingly, only about 9 inches more than the straight gas Civic.
The instrumentation is interesting and novel for the Hybrid. At the top of the right-hand cluster is a modern-day version of the old car ammeter with LCD segments indicating charge (CHRG) in green and assist (ASST) in blue (rather than the old discharge). With a normal start using the IMA it shows an ASST, which increases during acceleration. In cruise there is a small CHRG fed back to the batteries, and in braking there is a full CHRG. If the IMA batteries are low in charge there is also a conventional, tiny, 12-V lead-acid starting battery and motor.
Below the speedometer there are indicators with the capability of tracking two different "trips" with distances and average fuel consumption, and there is also a strip indicator that displays instantaneous fuel consumption, calibrated from 0 to 120 mpg. I found the indicator a little distracting just as I used to with vehicles equipped with vacuum indicators to help you drive most economically -- but no doubt you would get used to it. An economy shift indicator is also added to the 5-speed manual version.
The Honda Hybrid is equipped with 14 inch P185/70 "Low-rolling-resistance all-season tires" which obviously help optimize the fuel consumption...but in my neck of the woods, where we average about 75 inches of rain a year and where it is not unknown for there to be times when it is coming down at a 2 inch/hour rate, they looked to me like easy hydroplaning victims. I guess "all-season" can depend a lot on where you live!
Driving the Honda Civic Hybrid was a great experience, great fun, but is it the vehicle for me? I drive cars hard: It was the way I was taught to drive to get from A to B with the most dispatch in days when there were no highway speed limits and I was licensed to drive under blue lights. I've always maintained that I would never recommend anyone to buy any rental car I've ever driven, and with the Hybrid I'm afraid that I would over-drive the vehicle to get the performance I need to have. I would certainly have to change out the tires as winter comes on and the real rains arrive -- but those replacements would be a great deal cheaper than the $160 I have had to pay for the performance 17 inch tires on my present car.
But 650 miles on a tank of regular unleaded gas is so tempting…so are both the federal and state tax monies that I could get back…maybe another 2 or 3 years with 20 - 30 more hp added will convince me to be a little more permanently green, or at least green in town. Until then it's got to be another V-6.
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