2010 Honda Insight vs. 2010 Toyota Prius Comparison Test

At the launch of the 2010 Toyota Prius, Bob Carter, group vice president and general manager for Toyota Motor Sales U.S.A., tells us, "We'll face two challenges when the Prius goes on sale: the economy and the 2010 Honda Insight.

"The good news for consumers is that the market has plenty of room for both the Prius and Insight in their respective segments," Carter adds. "Based on our 2010 projections, the Prius can achieve a theoretical 7 percent share of the industry's largest segment — midsize sedans. In the second-ranked compact class, the Insight could achieve a 5 percent market share."

So it'll be a nice, peaceful coexistence for these two hybrid cars that just happen to look almost exactly like each other. Don't believe that? Neither do we.

As the U.S. economy continues its topsy-turvy performance, nobody's market share is safe. So it actually matters which hybrid car is better — the 2010 Honda Insight, which went on sale March 24, or the 2010 Toyota Prius, which hits dealers in late May.

The Insight has already proven itself against the 2009 Prius. But now that the 2010 Toyota Prius has appeared with its bigger engine, all-new chassis and 50-mpg EPA-combined fuel economy rating, it is a much tougher hybrid cookie (bursting with high-fiber organic oats and fair-trade chocolate chips!).

Let's Get Our Priorities Straight
We'd like to think the winner of this test will be the hybrid car that we truly enjoy driving — the one that makes us forget about the heavy cache of nickel-metal hydride batteries stuffed under its cargo floor. But instead let's consider the real reasons people buy cars like the 2010 Honda Insight and 2010 Toyota Prius.

Fuel economy is the big factor here, so just like in the earlier Mk II Insight-versus-Mk II Prius battle, we're weighting it 25 percent in the final scoring of our comparison, using the EPA rating for combined mpg, which has become a reliable indicator of real-world fuel economy since the EPA recalibrated the test.

Pricing counts just as much, especially since the Insight's mission is to deliver hybrid technology on the cheap, while the Prius (for all its pomp and mpg) has always been a relative bargain among midsize cars. Feature content and test-track performance are secondary considerations here, so we're weighting them just 15 percent apiece.

We've halved the number of ratings-worthy top features in this test, because these particular models of 2010 Toyota Prius and 2010 Honda Insight cars are light on feature content. Our Insight is an LX, the leanest version of Honda's inexpensive hybrid that we've seen thus far. It still has power accessories, air-conditioning (an automatic system at that) and a CD-equipped stereo with an auxiliary jack, but it lacks staples like cruise control and stability control, and wears steel wheels. You can't knock its $20,470 price tag, though.

Our 2010 Toyota Prius is a base model, meaning it has 15-inch cast-aluminum wheels (instead of the 17s on the Touring model), halogen headlamps (instead of LEDs) and cloth interior upholstery. It also has the equivalent of the 2009 model's Package #3, which provides upgraded JBL audio and Bluetooth, but none of the other new-for-2010 Prius options like the solar panel in the roof or the self-parking system. Nevertheless, this Prius is better equipped than the Insight, though, since cruise, stability control and a keyless ignition system are standard on every 2010 Prius.

Toyota hasn't released pricing for the 2010 Prius yet, so we've pooled the sharpest data minds at Edmunds.com and come up with an estimate. If Toyota keeps prices at 2009 levels (and that's likely), this car would have a $24,220 base price. Adding the option package ($1,350), our tester should cost about $25,570. (Recent reports suggest that Toyota might drop the price on the 2010 Prius to compete better with the Insight. Even if our number is a little high, however, you'll see that it doesn't hurt the Prius in this test.)

A Hybrid for Commuting
As hybrids go, the 2010 Toyota Prius doesn't have many liabilities. Whereas the second-generation Prius offered merely passable transportation for commuters, this one feels at ease on the freeway whether you're crawling in gridlock or cruising at 75 mph.

The stiff new chassis gives Toyota's hybrid hatchback a stable and refined ride on a par with other midsize cars. Road noise is better controlled, too, at least with the standard P195/65R15 89S Yokohama Avid S33 tires. The electric-assisted power steering still lacks feedback (of any kind), but between a new rigid mounting system and extra steering caster, the wheel seems more secure in our hands, with a heightened on-center feel. The driving position still isn't perfect, but the new seat design and telescoping steering wheel are a big improvement.

Passing maneuvers were taxing in the 2009 Prius, but by dropping an Atkinson-cycle version of its ubiquitous 1.8-liter inline-4 engine into the 2010 Prius, Toyota has mostly solved that problem while raising fuel economy to boot.

Rated at 98 horsepower at 5,200 rpm and 105 pound-feet of torque at 4,000 rpm, the 1.8-liter has a meatier torque band than the old 1.5-liter, and this means it's now operating at lower rpm most of the time. Only when you hammer on the throttle on a steady uphill grade do you really hear the engine working. Notably, this gasoline engine doesn't use any power-robbing accessory belts (thanks to the use of an electric water pump) and then incorporates typical diesel engine technologies like exhaust gas recirculation and exhaust heat recovery to cut fuel consumption further.

Total system output for the 2010 Toyota Prius is 134 hp once you add the 27-kilowatt (36-hp) battery pack that powers the car's front-wheel-drive electric motor. This motor is part of a complicated transaxle that includes an additional generator motor and the planetary-type continuously variable transmission (CVT) responsible for blending the car's gasoline and electric power sources. The transaxle is 20 percent lighter for 2010, says Toyota, which reduces torque losses.

From the driver seat, we notice the transitions between all-electric and gas-electric motivation are smoother, to the point that we're scarcely aware of them during a numbing freeway commute.

The Driver's Hybrid, if Such a Thing Exists
Compared to the Prius, the 2010 Honda Insight is a lot less complex, at least in the drivetrain department. It has an eight-valve SOHC 1.3-liter inline-4 engine rated at 88 hp and 88 lb-ft of torque. It also has a CVT. Between the engine and the CVT is a small electric motor. It can't motivate the Insight on its own as frequently or as fast as does the Prius motor, but when it joins forces with the gas engine, it provides the compact front-wheel-drive hatchback with a respectable 98 hp at 5,800 rpm and 123 lb-ft of torque from 1,000-1,500 rpm.

It's a stretch to call the Insight quick, though. It takes effort and plenty of revs to maintain speed on a mountain pass. To its credit, the engine is not unpleasant to the ear, and the CVT responds quickly to changing throttle demands. The blending of gas and electric power is seamless enough, but the car feels jerky coming out of idle from a stop.

Yet, you want to forgive any accelerative shortcomings when you realize that the 2010 Honda Insight has genuine steering feel — something we'd forgotten could ever exist in a hybrid. In addition, the suspension is tuned so you feel some connection to the car's P175/65R15 84S Dunlop SP31 tires and the asphalt under them.

Of course, if you start making real demands on the Insight on some twisty road, it brushes you back with understeer and body roll. At a sane pace, though, it's an unexpectedly personable hybrid car. An ergonomic driving position, complete with three-spoke wheel, puts you in the mood to befriend it.

The downside to this approach is that an afternoon commute in the 2010 Honda Insight is not entirely relaxed. Like every inexpensive Honda of the last half-century, it rides firmly and has lots of road noise.

Unlikely Track Star
As much as we like the way the Honda Insight drives, it can't fend off the 2010 Toyota Prius at our instrumented testing facility. It earns the higher slalom speed (60.9 mph versus 59.1 mph), but only because the Prius' stability control can't be switched off.

On the skid pad, the Toyota exploits its wider tires to deliver 0.78g of cornering grip to the Insight's 0.75g. The Prius is also 10 feet better than the Insight in braking — 118 feet versus 128 feet — and with four-wheel discs, it's less susceptible to fade.

There's also a big gap between the 0-60-mph times of these hybrid hatchbacks, as the Prius gets to 60 mph from a standstill in 10.1 seconds (or 9.7 seconds with 1 foot of rollout as on a drag strip), while the Insight needs 10.9 seconds (or 10.5 seconds with 1 foot of rollout).

As evidence of the Honda's fighting spirit, though, it narrows the gap by the quarter-mile mark. The Prius goes through in 17.3 seconds at 79.7 mph, while the Insight is there in 17.9 seconds at 78.2 mph.

The MPG Gap Shrinks
More interesting is what happens when we take the hybrids on a 115-mile test of fuel economy. Circumstances kept us from using our customary suburban loop in Southern California, so instead we improvised a route that's approximately 60 percent highway.

This approach tends to favor the 2010 Honda Insight, which sees its best mileage on the highway, based on the EPA rating of 40 mpg city/43 mpg highway/41 mpg combined that Honda predicts for it. In contrast, the 2010 Toyota Prius sees its best mileage in low-speed city driving, where it can scoot along in all-electric mode. Its EPA rating predicted by Toyota is 51 mpg city/48 mpg highway/50 mpg combined.

Even so, we expect the Toyota Prius to have a major advantage, since by the numbers, it's the more fuel-efficient car. During our drive, we call a moratorium on wide-open throttle, sync up use of the automatic climate control and the "Eco" modes of these CVTs, and charge one editor with a steady hand to take on the task of refueling.

Final score? Insight: 51.2 mpg. Prius: 52.2 mpg.

Different Kinds of Bargains
So the 2010 Honda Insight LX is nearly as fuel-efficient as the 2010 Toyota Prius, at least in our unofficial real-world test. It also costs $5,100 less. And we like how it drives, so much so that it's the unanimous personal pick of everyone involved in this test.

Yet the 2010 Toyota Prius wins this comparison by 7.6 points, because it's the better of these two hybrids. It's quicker, it stops shorter and, with its smoother ride quality and quieter cabin, it's the one you want to be in when you're commuting. In the right hypermiling hands, it will probably return better fuel mileage, too. The Prius is also a bigger car with a backseat that fits real adults, plus a hatch that will let you load a Labrador.

A hard look at the true costs of hybrid car ownership will likely lead you to conclude that the 2010 Honda Insight is the more sensible choice, simply because you can buy a lot of gas with the money you save. (By our math, you'd have to put more than 580,000 miles on a 2010 Prius to make up the difference.) Although this argument might appeal to your inner economist, it doesn't get at the day-to-day reality of living with these hybrids.

Sure, the 2010 Honda Insight might be cheaper and a little more fun, but for 95 percent of your motoring existence, the more practical 2010 Toyota Prius awaits, ready to serve your every commuting need. It also happens to be the more iconic of these two cars, and regardless of what anyone tells you, image matters when you're living with a hybrid.

The manufacturers provided these vehicles to Edmunds for the purposes of evaluation.

There's a $5,100 price difference between our 2010 Honda Insight and 2010 Toyota Prius test cars, and it's pretty obvious when you start looking at equipment lists. Even our lightly optioned Prius tester has significant advantages in this department. Although feature content is a secondary consideration in this comparison test, we've picked five we wouldn't want to live without in a hybrid.

Features

Key:
S: Standard
O: Optional
N/A: Not Available

Bluetooth: Hands-free phone use is fast becoming the law of the land, and we find in-car interfaces easier to use than headsets. Our Prius has it as an option, but on the Insight, it's only available with the navigation system.

Cruise control: It's nothing for us to put 1,000 miles on a car in 24 hours, and sometimes our right foot needs a break. The LX version of the Insight doesn't have cruise, so get the EX if you want it.

Keyless ignition system: Walk up, open the door, press the start button and go. No fumbling with keys at all. This is how life will be for every 2010 Toyota Prius owner. Insight owners still have to use a key.

Stability control: We dislike undefeatable stability control on sport sedans, but these hybrid hatchbacks are far from sporty and can really benefit from this active safety net. It's not available on LX versions of the Insight.

Tachometer: No matter how many electric motors are assisting, you're still in a car with an internal combustion engine, and we want to know how fast it's revving, damnit! In this regard, the Honda Insight is our favorite.

Vehicle Testing Assistant Michael Magrath says:
As you can imagine, the Inside Line offices are teeming with car chat. The subject really doesn't matter; if it's got wheels and a motor, we're going to be talking about it sooner or later. And so you can imagine how popular I was the day I came back from driving the 2010 Toyota Prius and 2010 Honda Insight — I was the first to return.

But, contrary to my nature, I was soft-spoken. Reserved, even. I thought I just needed more time to process the information I'd absorbed after a few hundred miles of hybrid-lovin'. My brain was telling me the Prius was the better car; I wasn't buying it.

When I finally spoke a few hours later, the words poured out: "The Insight is like a real car. It drives like a Honda, feels like a Honda and, generally, works just like a real Honda, except the brakes feel weird. The engine always spins so that doesn't get weird. The 2010 Prius is like the old one but with more power, better range before the gas engine kicks in and an all-electric mode that's pretty neat. And it's quieter. Much quieter than the Insight. Lots of insulation from wind, road and drivetrain noise. And the interior space is better. My shoulders don't feel cramped and the seat is better for extended stints behind the newly telescoping wheel. My neck's not cramped in the backseats like in the Insight.

"The 2010 Prius," I concluded, "is the closest we're going to get to private, driverless capsules that transport us anywhere we want. There's no driving involved. It's the ultimate commuter car for people who would take public transportation if it was convenient and efficient and didn't smell."

Sure, the 2010 Insight is cheaper by a few grand, but the refinement, amenities and yes, the power, afforded by the new Prius will be well worth the extra cash.

Final Rankings

Personal Rating (2.5%): Purely subjective. After the test, each participating editor ranked the 2010 Honda Insight and 2010 Toyota Prius in order of preference based on which he or she would buy if money were no object.

Recommended Rating (2.5%): After the test, each participating editor ranked the hybrids in order of preference based on which he thought would be best for the average person shopping in this segment.

28-Point Evaluation (15%): Each participating editor scored the hybrids based on a comprehensive 28-point evaluation. The evaluation covers everything from engine performance to rear-seat comfort. Scoring is calculated on a point system and subsequently averaged based on all test participants' evaluations.

Feature Content (15%): For this category, the editors picked the top 5 features they thought would be most beneficial to someone shopping for a hybrid in the $20,000-$25,000 price range. For each car, the score is based on the number of actual features it has versus the total possible (five). Standard and optional equipment are taken into consideration.

Performance Testing (15%): Both cars are put through a comprehensive battery of instrumented tests, including 0-60-mph acceleration, quarter-mile runs and panic stops from 60 mph. They are also run through a 600-foot slalom course to test transitional handling, and around a skid pad to determine ultimate grip. Each car is awarded points based on how close it comes to the better-performing hybrid's score in each category.

Fuel Consumption (25%): The scores listed are the result of a simple percentage calculation based on the car with the highest EPA combined fuel economy rating (55 percent city plus 45 percent highway). The more efficient Toyota Prius (50 mpg combined rating) received a score of 100, with the Honda Insight (41 mpg combined) receiving a lesser score.

Price (25%): The numbers listed are the result of a simple percentage calculation. Using the "as tested" prices of the actual evaluation vehicles, the cheaper Honda Insight ($20,470) received a score of 100, with the more expensive Prius ($25,570 — estimated) receiving a lesser score.