Wrench smart – driver smarter – save fuel

I want to try to list steps that car makers could/should take to improve the fuel efficiency, in approximate order of cost:

• The most obvious improvement to cars, would be to mold the plastic on the front of the vehicle to be smooth and round, with grill openings that are sized (and placed) only as required to cool the engine. Some new plastic bumper covers and grill pieces could be snapped onto cars. Flush covers should be used on all lights. Fairing pieces could be added to side mirrors. Hood gap gaskets, and streamlined wheel covers are easy, too.

• Sealing all the seams and joints (with gaskets/backing flanges) in the high pressure areas of the vehicle, & flush side glass.

• Smooth floor pans with no sharp protrusions — this is part of the drag just as much as the parts of the car that can be easily seen. Smoothing the underside with covers (like the GM EV-1, the 3^rd gen Prius, the 1939 Maybach, as well as the VW 1 Liter car, the 1937 Schlör “Pillbug” and the Aptera).

• Transmission ratios should be optimized for efficiency at normal driving speeds. Higher gearing with 6-7 speeds would be optimal (smaller engines need more gears to work efficiently); or CVT transmissions.

• Narrower and lighter, LRR (low rolling resistance) tires should be used. Use very high quality wheel bearings (ceramic or precision steel) and make alignment robust and easy to service.

• Average & “instant” MPG displays, that are on all the time; so the driver can compare them. The new Honda Insight, the 3rd gen Prius, and some Ford models, have excellent displays that help the driver be more efficient; with different color backgrounds indicating how efficiently you are driving.

• Throttle control (rather than cruise/speed control!) that maintains even throttle in a user-set speed range, with minimal throttle increases to maintain the speed in that range. This should also decrease throttle and coast when the speed is higher than the user set range.

• Tire pressure monitor, that warns the driver when the tires get below the recommended pressure (which could be adjusted upwards if the driver wants to run a pressure up to the tire sidewall maximum).  Or better yet: fill tires with foam, so they would never deflate, and minimize rolling resistance.
  

• Efficient & effective fresh air flow through the vehicle, with intakes on a high pressure area, and exhaust vent(s) out the back of the vehicle into the low pressure wake zone, providing passive ventilation; and also reducing aerodynamic drag.

• Coat all the window glass to exclude as much heat as possible. With effective fresh air flow (see above) this may completely avoid the need for A/C (see below).

• On defrost mode, the A/C should only come on automatically at maximum defrost (if at all), and it should be on a timer of ~1 minute, and it should always be toggled on/off by the driver. I would prefer to make A/C on the defrost setting optional.

• Efficient lights such as LED’s and HID, that use a little power as possible while functioning as well (or better) than incandescent lights.

• Lower consumption electronics, such as A/C, fans and audio systems. Some/all of these could be powered by solar PV panels with a robust battery system; even in conventional internal combustion engine (aka ICE) powered cars.

• Active grill, that opens when more cooling air is needed, but remains closed – and is more aerodynamic most of the time. This can also be done passively with the right airfoil shapes that effectively closes off air flow when the velocity goes up.

• Wheel alignment and brake drag needs to be minimized, easy to adjust, and robust – to maximize rolling efficiency.

• Fully ducted engine cooling system, with the intake down low on the front, and the exhaust flows into a low pressure zone; minimizing the size of the radiator and the reducing the “internal” drag as much as possible. The Britten V1100 (racing) motorcycle is an good example of how this could work.  NASCAR has shown that for a fully ducted cooling system, you only need 16 sq in for every 100HP.
  

• Video cameras and screens in place of side mirrors. This would help a lot with aerodynamics.  An example of this starts in post #167: http://ecomodder.com/forum/showthread.php/scion-xa-aero-mods-2969-17.html

• Automatic engine shut off and start up; at least with CVT (or automatic) transmissions — and possibly with standard shifts, based on having both the clutch and the brake applied? The Toyota/Scion iQ will have this feature.

• Lean burn in low vacuum conditions. Use variable valve timing to gain efficiencies.

• Store hot coolant in a vacuum insulated tank, to speed up warm-up time; a-la what the 2^nd generation Prius does. Or, do what the 3^rd generation Prius does: heat the coolant quickly using the exhaust heat. Preheating intake air would also help fully vaporize the fuel; making it higher efficiency.

• Tighten up wheel openings, and always use aerodynamically designed wheels/covers, with rear wheel skirts (at least optionally).

• Make roof racks removable. Years ago, I saw a “papoose” add-on storage system that locked onto the back of the car, with a single caster wheel to support the weight — it tucked completely into the air flow behind the car, forming a boattail; and it would be a great way to add storage space when needed; that did not affect how you drove very much. It could actually greatly improve the overall aerodynamic drag of the vehicle.

• Regenerative shock absorbers: MIT has a method of using hydraulics to drive a generator, eliminating the need for a mechanically driven alternator; or, to charge the electric drive (aka traction) batteries. These can also be used to lift and level the vehicle, to improve aerodynamics under different loads.

• Use a composite wheel/tire that has low weight, very low rolling resistance (by being strong enough to stay round), and low aerodynamic drag, no worries about inflation — and tune the suspension to work with said wheel/tire. (see item above) This could gain even more energy, since very little would be damped by the tires.

• For new 4-cylinder internal combustion engine designs, the crankshaft could be split with a hydraulic coupling that can automatically disengage two cylinders completely; saving all the pumping and friction losses, for situations when 2 cylinders are enough to provide the required torque to move the vehicle. There are also cam-driven designs that about double the efficiency of the ICE.

• Nissan is (supposedly) going to reduce their cars weight by ~15%. I think all cars could be reduced by 20-30% with smarter steel fabrications, smarter use of materials. Here’s a site that shows a steel chassis that is 25% lighter and nearly twice as stiff/strong as a conventional steel chassis:

  http://www.bluescopesteel.com.au/go/news/ultra-light-steel-auto-body-ulsab-project/

• Multiple car door latches could be used to increase strength & safety of the chassis — helps to further reduce weight, increase strength & rigidity, without requiring an unusual entry method (such as the VW 1 Liter car or the Loremo).

• Make every vehicle with a plug-in electric w/ serial hybrid ICE drive train, with regenerative braking. Use a cam driven engine that spins the armature and the stator in both (counter-rotating) directions, to charge the traction batteries. The engine could have rotary valves to reduce parasitic losses. It would run at it’s ideal RPM to drive the torque load of the alternator.

• Rework the overall shape of the vehicle to reduce drag. Cd of 0.13 – 0.25 are achievable! The 1937 Schlör“Pillbug” seats 5-7 people and has a Cd of 0.13 – this car should used a model!

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For more pictures, see the gallery at the end of the post.

The other day I finally got behind the wheel of a the much-lauded Jetta TDI, aka the diesel that could. Despite efforts from all the automakers to get diesels a favorable light in the North American market, it has always been Volkswagen holding the reins and beating back competitors.

Now, the new generation of 50-state legal diesels is selling like hotcakes while proving that fuel economy and power are not incompatible goals. Despite the fact that many manufacturers are still shying away from importing their diesels to the United States, VW has proven over the last 20 years that they are willing to stick out the relationship through thick and thin, and are finally reaping the rewards.

What is the 2009 Jetta TDI?

The flagship of Volkswagen’s diesel efforts in the United States, the 2009 Jetta TDI packs a lot of punch into the manufacturer’s stedfast sedan. After spending some time off the market due to evolving emissions regulations and the push to release 50-state clean diesels, the Jetta has returned it’s fuel economy champion to the market with a 2.0l engine delivering 140 hp and 236 ft-lbs of torque.

This car definitely isn’t your father’s Volkswagen Rabbit. Despite VW’s legacy of diesels that smell funny and couldn’t kick themselves in the butt to get up a hill, the company reinvented the TDI brand into something now more closely related with high torque and driving excitement than penny pinching and hard starts in the winter.

However, the car hasn’t completely lost its fuel economy roots. The rather large and powerful sedan still manages to impress most drivers with EPA ratings of 29 (city)/40 (highway) mpg with an automatic transmission or 30/41 mpg with a stick shift. Despite using slightly more expensive diesel gasoline, the car is poised to save drivers big over its gasoline siblings, which only manage ratings averaging 21 (city)/30 (highway) mpg.

Who should consider buying the new Jetta TDI?

Despite Volkswagen’s once-coveted position as the “car of the people,” the brand is now a little more up-market, with the Jetta TDI setting you back at least $22,270 ($1,100 more for the automatic transmission). That makes the TDI more expensive than Honda Insight and Toyota Prius hybrids.

Many buyers who are interested in fuel economy but need the space of a family sedan will likely find themselves looking at the Insight, Prius, and Jetta TDI. If thrift is all you’re worried about, the Insight or Prius will likely win, as they return better gas mileage for less money on cheaper fuel. However, that’s rarely the whole story.

The Jetta TDI is perfect for the efficiency-minded driver who desires both a spirited vehicle and a manual transmission, something the TDI distinctly offers and other fuel-efficient competitors fall short on delivering. It is this balance of fuel economy, oomph, and driving excitement that make the Jetta TDI worth looking at.

Jetta TDI Fuel Economy Report

Unfortunately for this review I was saddled with the automatic DSG transmission and did not get to take a crack at the stick shift version of the 2009 Jetta TDI. Although the automatic only averages 1 mpg less than the stick shift in the EPA test cycle, an experienced ecodriver can easily achieve much better mileage in a stick shift than an automatic.

That said, I was pleasantly surprised with my ability to surpass the EPA ratings in the DSG-transmission 2009 Jetta TDI with only mild ecodriving techniques in mostly suburban driving.

Over a few hundred miles of mostly short trips in suburban conditions I managed a respectable 41.1 mpg, 25% over the EPA combined rating of 33 mpg. To achieve this number I used only moderate ecodriving techniques mixed in with a lot of spirited driving. Though I was held back a bit by the automatic transmission, with a stick or more advanced techniques higher numbers are definitely a possibility with this car. Unlike its hybrid competitors, the TDI doesn’t struggle to soar past its EPA ratings when driven carefully.

However, during short trips and when making use of the overabundant power output of the diesel engine, mileage can be an issue, with some of my trips coming in at less than 35 mpg. As easy as it is to get great mileage with this vehicle, it is just as easy to see it all slip away during one spirited launch from a stop light.

In the end, more than many other cars’, the 2009 Jetta TDI’s fuel economy is what you make of it.

Overall Impressions of the 2009 Jetta TDI

While I focused on fuel economy during my time behind the wheel, I did not ignore the rest of the car. The 2009 Jetta TDI is a roomy, attractive sedan that is both comfortable to be in and to drive. The vehicle holds the road and gives you a feeling of confidence as you test the more spirited aspects of the car.

The 140 hp and 236 ft-lbs of torque really make themselves noticed when you put the pedal to the floor, tempting you to waste more fuel than you most likely should. When driving the car, it becomes clear that Volkswagen sacrificed a fair amount of fuel economy in the name of fun, which is sure to set the vehicle apart from some of its hybrid counterparts.

Storage room is ample and it is easy to fit five people in the car, though like many smaller sedans, it might not always be the most comfortable seating arrangement. Despite a surprisingly long trunk, I found it a little difficult to use for my normal hauling because the dimensions were narrower than I am usually treated to. Luckily, folding rear seats making hauling most things a fairly painless task.

Despite the fairly attractive gauges, I found myself constantly annoyed that the central information display would only display one thing at a time. This meant that I could only look at current fuel economy or trip fuel economy, but never both at the same time, which, as an ecomodder, left me constantly toggling between the two screens in order to get the information I needed.

The other main point of difficulty with the car was that with only 1000 miles on the odometer the stereo decided to randomly spike to 100% of volume. This made listening to the radio impossible and I eventually gave up fiddling with the knobs to turn it back down and just went without the built-in satellite radio for the remainder of the test drive. This may be an isolated incident, but for someone who still has doubts about VW’s ability to produce high-quality vehicles, it was a troublesome one.

Overall, the car was very solid and certainly wins my thumbs up as a sedan for performance, comfort, and handling.

Conclusion

If you’re looking for the most fuel-efficient vehicle you can get, the 2009 Jetta TDI is probably a bit overpowered for you. Despite the car’s ability to quite easily exceed the EPA ratings, it will still struggle to compete with hybrids like the Prius and the much more affordable Honda Insight.

However, if you’re looking for an attractive, fun, and comfortable car that can get good mileage without the attached stigma of “eco-nerdiness,” this might just be the car for you. The sedan sacrifices something in utility compared to hatchbacks like the VW Golf or Toyota Prius, but the Jetta is larger than you might at first expect and can handle all of the tasks you would expect a family sedan to be able to.

In the end, the 2009 Jetta TDI really stands alone in its attention to both fuel economy and above average performance and comfort.

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In an effort to increase the blog’s focus on ecomodding and some of the great content that comes out of our users, I’ve decided to begin a series of posts on an ongoing project coming out of my own garage. The idea of swapping a Honda Insight hybrid drivetrain into my CRX began at this year’s Green Drive Expo, where despite my good mileage I realized I just couldn’t compete with the first generation Insight.

With that in mind I had two options: buy an Insight or ecomod the CRX. Buying an Insight would’ve been easier, but more expensive, less fun, and frankly my CRX is still in great shape. So, I decided to shop around for a totaled I could strip down for parts to recycle into my CRX.

Having found one, the swap became just a matter of doing it, which is where I currently am, and that’s where this update comes into play. The swap is half-finished, with all the old having been stripped out with the new ready to go in.

However, removing everything is clearly the easy part, with the second half of the project being the troublesome attempts to put things back together and make them play nice with each other. At this point there isn’t much to say, but in the upcoming posts I will take you through how I tackle several problems in making this whole thing come together.

Look out for upcoming posts on:

• Custom engine mounts
• Integrating the obd2 wiring system into the obd0 harness
• Adding the IMA hybrid system
• Tweaking the IRX for superb gas mileage

To stay up to date on the nitty-gritty, follow along with my project thread on the forums.

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Honda has had a long legacy in racing, from its early days racing motorcycles to its recent success as an engine supplier to other top-teir racing teams. However, last year Honda ended it’s relatively short-lived F1 team under cost-cutting pressures brought on by the larger downturn in the automotive industry.

Now, Honda has taken that team of 400 engineers and put them back to work squeezing every last ounce of efficiency out of their passenger vehicles. As investment fund manager Masayuki Kubota told Bloomberg:

“Automakers that are able to spare their resources for advanced and environmental technologies will eventually become the winners at a time when one breakthrough technology will make a huge difference.”

In recent years, Honda has made a name for it’s by rejecting may of the current trends in environmental engineering like plug-in hybrid electric vehicles (PHEVs) and pure battery electric vehicles (BEVs). Instead, Honda has been working hard on perfecting it’s market-leading fuel cell technology and redoubling efforts to improve the internal combustion engine (ICE).

Most companies act as if they have given up on the ICE, but according to Honda the ICE will remain the dominant form of propulsion for the next several decades. Even if Japan, America, and Europe phase out the ICE relatively quickly, emerging markets in India and China will rely on cheaper ICE technology for decades to come, making efficiency gains important to a long-term, global approach.

Honda has clearly put most of their eggs in the ICE basket and only time will tell if it pays off. Either way, Honda is certainly putting its best foot forward in accomplishing its goal.

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