Insight 1G: first-gen Honda Insight with diesel upgrade gets 80 mpg
Ever heard of the Insight 1G? Sounds like the name of a first generation of the high-efficiency hybrid, right? It is, but the twist here is that the 1.0-liter, 70 hp gasoline engine has been swapped out in favor of a oil-burning 1.2L PD TDI from Volkswagen, specifically the Lupo 3L. How does the diesel swap make the car run? Excellent, says the Red Light Racing team's website. In fact, they claim they're getting 80 mpg without the hybrid portion of the powertrain in operation (It appears the team is using a manual Insight, which was rated at 53 mpg combined, by the EPA). They expect a further fuel economy boost of around 15 to 20 percent once the bugs in the engine signal translator are worked out.
Speaking of bugs, the conversion hasn't exactly been easy, and the team has set up a list of technical difficulties (and solutions) here. Jake Staub, the team's lead engineer, told AutoblogGreen that, "The main idea was to take existing hardware, hack it, and make a vehicle that could be produced by major manufacturers or individuals that would deliver tremendous fuel economy without a tremendous leap in technology. I believe we succeeded." Do you agree?
[Source: Red Light Racing]
Reader Comments (Page 1 of 2)
Dave 7:18PM (9/05/2009)
A hybrid system does the following for a gasoline engine:
1. Prevents the gas engine from wasting gas idling.
2. Reduces the amount of part throttle operation.
3. Allows the use of an Atkinson cycle by providing low speed torque.
4. Recovers energy through regenerative braking.
A diesel engine, however, uses much less fuel while idling, suffers from no throttling loss, and cannot be converted to Atkinson cycle.
So, the addition of a hybrid system is not as helpful to a diesel drivetrain. It provides regenerative braking and little else. (Of course, in a very large,heavy vehicle that does a lot of stop/go such as a bus or trash truck, regenerative braking is huge - that is why GM/Allison built the two-mode for such vehicles)
Of course, the Insight will get impressive gas mileage anyway, due to the excellent aerodynamics, low rolling resistance tires, and low weight.
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LaughingMan 3:02AM (9/06/2009)
You're right on all of these points, but you're missing a few very important advantages of a hybrid system.
Full hybrid systems like those used by Toyota, Ford, and the GM Two-mode system allow for engine to be halted as the car is in motion.
The most recent incarnation of the Honda IMA system has a similar mode of operation that allows for deactivation of all four cylinders while the car is in motion, but requires the engine to continue to turn over.
At speeds less than highway speed, these modes allow for hybrid systems to have an engine active duty cycle of less than 100% while the car is in motion.
Practically, this means that while the car is coasting or braking, the engine will burn 0 fuel instead of the small amount required to keep the engine turning over. It also means that if driven correctly, the electric system can even maintain the same speed or accelerate without the engine.
When people say that hybrid cars are best in stop-and-go traffic because they assume that the majority of savings are from idle-stop, this is actually far from the truth. The real savings comes from the fact that engines, diesels or otherwise, burn more fuel per mile at lower speeds than at highway speeds. Hybrid systems take every opportunity to reduce that inefficient low speed engine consumption to 0.
Modern diesels perform better than conventional gasoline engines in the city cycle, but they do not come close to hybrid vehicles in the city. If someone can implement a full hybrid system mated with a diesel, the biggest gains will be in the city and surface roads.
LaughingMan 3:12AM (9/06/2009)
I should also note that hybrid hypermilers have learned over the last 9 years to exploit this very feature on Insights, Priuses, and other hybrids. The Pulse and Glide technique relies on dropping into an engine-halted coasting state.
With this technique and a light foot, hypermilers have gotten the engine on duty cycle to 1/3 or less, and have racked up over 100+ MPG in stock Priuses and 80 MPG in a stock Ford Fusion Hybrid.
randomdude 5:14AM (9/06/2009)
"and cannot be converted to Atkinson cycle"
That's not true. All you need is a different cam shaft. It wouldn't be the proper Atkinson cycle, but it would work by the same principal (longer expansion).
Furthermore you say "Reduces the amount of part throttle operation". You can 'move' the load point and thus run the engine at a better efficiency. That's possible with a diesel engine, too.
Dave 5:37AM (9/06/2009)
I do not deny that the hybrid system will provide an improvement.
As I said, it will not be nearly as dramatic as the improvement in a gasoline engine.
And I question whether the ~30 gallons of diesel fuel saved per year would justify the cost (in dollars and energy used in manufacture) of the system.
downtoearth 11:50AM (9/06/2009)
randomdude:
>> "and cannot be converted to Atkinson cycle"
> That's not true. All you need is a different cam shaft. It wouldn't
> be the proper Atkinson cycle, but it would work by the same
> principal (longer expansion).
You're wrong, randomdude.
Doing so will make the exhaust gases pressure (thus their kinetic energy) not enough to drive the turbocharger (necessary in diesel engines cause the run lean mode with intake air excess most of the time). So you'd have to steal energy from the engine crank shaft to power the turbo, instead of recovering exhaust spare energy.
This is why diesels are not converted to Atkinson cycle.
Hybrid engines at the same time need no turbocharging, electric boost replaces it.
Chris M 6:01PM (9/06/2009)
Yes, it is possible to convert a diesel to run an "Atkinson Miller cycle". The original Atkinson engine used an ingenious and complicated mechanism that caused the power and exhaust strokes to be longer than the intake and compression strokes, extracting more energy from the expanding hot gasses. (The mechanism was developed to get around patents on the crankshaft!) Years later, an engineer named Miller realized he could get a similar efficiency boosting effect with a regular crankshaft engine by delaying the close of the intake valve, effectively shortening the compression stroke.
To convert a diesel to Atkinson-Miller operation would require both changes to the intake camshaft to delay intake valve closing and changes in the crankshaft to get sufficient compression and a longer expansion stroke. Such extensive modifications might not be worthwhile, especially for a turbocharged engine.
why not the LS2LS7? 10:17PM (9/05/2009)
You could make 80mpg on an Insight just through careful driving. It would be better to see this tested with EPA-style tests to see how the mpg really compares.
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Snowdog 10:57PM (9/05/2009)
So they put a Lupo 3L engine in a more aerodynamic body and get a little more MPG than a Lupo would get.
Yawn.
There is a guy with a ZX2 like mine that put on more aero pieces and fuel cut offs for pulse and burn savings. He gets 100MPG+ tanks with a 2.0L gas engine. I get about 25mpg.
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Steve 11:09PM (9/05/2009)
Hey bone heads, you obviously don't get the point of what they did.
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Rick 11:47PM (9/05/2009)
I'm thinking the point was somebody likes that diesel rattle and vibration and possibly they want to test out how tight all the dash screws are.
Dave 11:09AM (9/06/2009)
Theyve proven that you can spend $4000 to save $1000
Brilliant
Dave 11:58AM (9/06/2009)
PS-
Its already been done. A decade ago.
http://en.wikipedia.org/wiki/Partnership_for_a_New_Generation_of_Vehicles
The OEMs decided the benefits were outweighed by the cost.
Even in Europe and Japan, where fuel is far more expensive and diesel emmission regulations are less severe, OEMs have come to the same conclusion.
Nick 1:11AM (9/06/2009)
@Rick
Your comment highlights the belief of the majority of the population, that diesels stand for sooty, smelly and rattling motors.
Been living under a rock?
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Snowdog 10:11AM (9/06/2009)
Did you watch the video and hear the clatter coming out of the engine?
Did you know that this isn't a clean diesel, like the latest VW offerings but an old, non emissions controlled one?
This is a sooty, smelly, rattling diesel that they put into an Insight that people already got ~70mpg with (the manual version).
Jon M 12:54AM (9/06/2009)
Geez... I love the idea, but my GF's VW is a wreck as far as reliability and service are concerned. We were actually thinking of having her father's company (he's a CEO for a detroit firm that prototypes cars like Aston's and the Ford GT) swap out the drivetrain, engine, etc. for something from Honda or Toyota to make it more reliable.
Putting a VW engine in a Honda? It might be more efficient, but now it will need an extra $2000 in repairs every year...lol.
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OpenMinded Patriot 8:21PM (9/07/2009)
Carbabys = spam post. Link = Car Insurance BS page...
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Sam 3:46PM (9/06/2009)
Did you know that this isn't a clean diesel, like the latest VW offerings but an old, non emissions controlled one?
Actually it did have emissions controls in the original car that met the emissions standards of it's time. This included high precision fuel injection, an EGR system, and a Catalatyic converter. It's no clean diesel but it did come with emissions regulation systems and met it's emissions standards where it was sold.
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matthijs 6:37AM (9/07/2009)
Judging the above comments, did anyone read the website of redlightracing? The goal is to make a diesel-electric HYBRID. The fuel consumption will be 90 mpg city / 110 mpg highway (estimated). CO2 emissions: 63 g/km and to top it off it will comply with the Tier II Bin 5 Emission standards!
This was just the first run. When the team is finished it will be one of the best hybrids ever.
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why not the LS2LS7? 4:29PM (9/07/2009)
That engine will never meet T2B5. They're going to have to swap again.
And I'll tell you what, I'll congratulate them for reaching these brag figures when they reach these brag figures. In EPA-style testing.