The Drive to 35.5 Miles Per Gallon, Part One

Part One of this series introduces the context of an experience that our writer had at a media event sponsored by Bosch, and specifically looks at internal combustion technological improvements.  Tomorrow’s installment will delve into electrical system technologies that can also improve fuel economy.

By J. Smith


fueleconomyThis past spring, the Obama Administration announced more stringent fuel economy standards, which will require cars and light trucks to reach CAFE standards of 35.5 MPG by 2016.  And stringent emissions requirements are around the corner.  Auto Supplier Bosch wanted to showcase the technology it has been developing that will help meet that goal.  And they had cars in which to test said technology and a proving grounds site in the Mitten State.  And Autosavant has exactly one correspondent who resides in the Mitten State, hereinafter known as Michigan.  Hijinks ensue.

I had some trepidation about this assignment.  After all, fuel economy events are hardly the stuff of which dreams are made.  The last time stringent fuel economy and emissions regs went into effect, it gave birth to an era of leisurely performing, poorly running transportation-related devices—can we really call them cars?—that most enthusiasts recall only after waking in a cold sweat.  What future horrors wait in the shadows?  A new Malaise Era?

Several times during the event, Bosch claimed to be technology neutral.  This statement, however, may be a little less true.  Bosch had speakers address fuel systems, both gasoline and diesel systems, chassis control systems, including adaptive cruise control and automatic emergency braking, electrical systems, including Start-Stop systems and High Efficiency Alternators and Electric Power Steering.  All the speakers agreed that the ultimate move would be towards electric vehicles, although none of them could give a time frame for that transition.  Nor could they say how much all this technology would end up costing consumers, or when, if ever, that price would be set-off by lower fuel bills.  And some of the presentations added a factor of “extreme downsizing” for maximum fuel economy savings.

Despite this smorgasbord of approaches, two key items during the day’s presentations were relegated to appetizer status: hybrids and battery systems.  The reason for this was quite clear: Bosch is not a major player in that area.  To be fair, one would not expect a major commercial enterprise to highlight technology areas outside its scope of expertise.  At the same time, Bosch’s roadmap to 35.5 is driven by their own technological and production expertise.  But the map to electric vehicles seemed a little fuzzy, particularly when all involved readily agreed that electrification was the ultimate objective.

Bosch believes, however, that the internal combustion engine will be around for decades while the transition to electric cars takes place.  It also believes that room exists for potentially large fuel economy increases with technological tweaking of our dear old ICE.  And all of the engineers I spoke with stated that, unlike the Malaise Era, this time there won’t be a trade-off between performance and economy this time around.


BMW 7-Series Active Hybrid

To prove the point, they had several vehicles on hand that exhibited one or more technical innovations that increased fuel economy at no penalty to performance.  Color me skeptical, I thought, as I headed out toward the test track with a flock of other scribes.  At the same time, if Bosch is right, the next decade may show that we can have the best of all possible worlds.

Bosch sees hybrids as an interim step on the road to full electrification of vehicles.  Along that road, it expects the proportion of hybrids to slightly increase over the next decade, with conventional gas engines to decline.  Diesel will sales will increase ever so slightly, but the big winner, at least according to Bosch, will be turbo-charged, direct-injection gasoline engines.  It expects these to become major, perhaps dominant, in the North American market in the next decade.

But engine technology is only part of the equation.  Increasing the gears in automatic transmissions will also yield better fuel economy.  Four-speed autos are on the way out, and even five-speeds will soon be displaced by six-speeds as the industry standard.  In addition, high-efficiency alternators, electric power steering, start-stop systems and adaptive cruise control will all play a part.  Putting all of the gains together in single vehicles will, according to Bosch, result in significant fuel economy gains with better performance than the cars of today.

But all of this comes at a price.  Bosch skirted around my question about cost, but it admitted that these applications would first be seen in high-end autos as a way of maintaining the performance that well-heeled consumers expect, while still meeting stringent emissions and fuel economy standards.  Buried in the speakers’ charts was another factor: dramatic downsizing.  The lower end of the car market, it seems, will have to downsize both engines and weight, in which case there will be a performance and comfort penalty, at least until the technologies displayed by Bosch become far less expensive.


Bosch, a leader in diesel technology, is naturally bullish about Rudolf Diesel’s engine.  Its people believe that diesel offers the best way to achieve large fuel economy gains with little to no sacrifice in performance.  It acknowledges, however, that it faces a formidable obstacle in that North American consumers have notable “resistance” to diesel engines.  Hmmm.  What could have caused that?  Outside of full-size trucks, not too many Yankees or Canucks go for oil burners.

Diesel Common Rail

Diesel Common Rail

Emissions issues also loom large for the diesel.  Diesels are also more expensive.  And typically perform worse than gas engines.  Bosch claims that the denoxtronic emissions system can scrub exhaust and improve fuel economy.  It also claims that the break-even point at which a consumer’s higher initial cost is recouped can be reached in as little as 7,500 miles per year once better depreciation is factored in.  Finally, Bosch believes that turbo systems can eliminate the performance gap with gas engines.

But how does it work in the real world?  I drove several TDI diesels at the Bosch proving grounds to find out.  First up was a Jetta wagon, with a 2.0-liter TDI with an auto tranny.  The first thing I notices was how quiet this thing was.  Right from start, it was muted, not at all like the clattering soot-belching machines of yore.  The low-end felt strong.  Right off the line, even with an auto, it pulled with tenacity.  My Focus has a 2.0-liter gas engine and let’s just say it doesn’t have this kind of off the line pull.  Acceleration was acceptable, not spectacular, but it felt much stronger because it had oodles of torque.  And the EPA says it get fuel economy of 30-MPG city and 42 MPG highway.

Next up was a Jetta “Sidewinder” especially prepared by Banks Power Engineering, which builds performance diesel applications.  It accelerated much stronger than the other diesel Jetta.  The course Bosch set up for us was a straight-line run, with a few street turns, so I had no opportunity to test the handling.

I then sampled an Audi Q7 diesel with a 3.0-liter TDI diesel V-6.  According to the rep, it has a 50% take rate, meaning that half of al buyers opt for the diesel.  It kicks out 225 HP, which doesn’t seem like a lot for this large of a vehicle.  But 406 pound-feet of torque sounds much better.  Once again, this was quiet and had loads of kick off the line.  Acceleration felt strong because of all that torque, but didn’t feel particularly fast.  It had a “D” mode for more leisurely shifts and an “S” mode for higher RPM shifting.  “S” mode seemed to shave a little off the 0-60 time, but I had no way to measure it.  What I found most disappointing had nothing to do with the engine.  The interior had some cheap plastics and a clunky “thump” when the door shut, both of which were completely inappropriate in this price range.  The EPA rates this as 17-MPG city and 25 MPG highway.

This generation of diesels impressed me with strong acceleration and quiet operation.  Of course, all of that comes at a price.  And a certain inconvenience, as not every gas station carries diesel, and the ones that do usually only have one pump.  But for those who want maximum MPG with minimal penalty in performance, the future of diesels seems bright.

Gasoline direct-injection with turbo-charging

Gasoline Direct Injection

Gasoline Direct Injection

The oldest option to increase fuel economy is reducing engine displacement.  Needless to say, this usually results in decreased performance.  Bosch claims that new technologies can change this equation, so that engines can decrease displacement and increase fuel economy, but without the trade-off in performance.  Thus, V-6 engines can replace V-8s and I-4s can replace V-6s, and get better MPG and suffer no performance penalty.

I tested two recent Ford products with a 3.5 liter EcoBoost V-6, which Bosch helped develop.  The 3.5-liter EcoBoost features direct-injection with twin turbo-chargers.  It cranks out 355 HP and 350 pound-feet of torque, and Ford claims it give V-8 performance with V-6 fuel economy.  I can’t vouch for the MPG, but the performance was definitely brisk.

First up was a 2010 Lincoln MKS with the 3.5-liter EcoBoost and all-wheel drive.  Opinions vary on the grille, but I like its curves.  On the inside, it started and operated with the expected luxury hush.  But when you push the gas pedal, it jumped out like a rocket.  This thing moves up to 75 MPH—the top speed allowed by the barristers—like nothing.  No turbo lag here, boys.  You could hear a little growl under full acceleration, but not much.  Frankly, I’d prefer a little more growl, but I suspect the typical luxury class buyer does not.  At any rate, this car surprised me enormously.  It rates 17-MPG city and 25-MPG highway.  In comparison, a Chrysler 300 with AWD and a Hemi gets 16 MPG city and 23-MPG highway.

Next was a Ford Flex, which seems massive an imposing in its lego-sculpted slab-sides and right angles.  Interestingly, it’s not as big as it looks.  It’s 202” long by 76” wide and the MKS, which seems much smaller, is 204” long by 76” wide.  At any rate, with the 3.5-liter EcoBoost, this thing hustles with impressive eagerness.  It gets 16 MPG city and 22-MPG highway; a main competitor, the Chevy Traverse, gets 16 MPG city and 23-MPG highway, but I’d wager it doesn’t move quite as quickly as the EcoBoost Flex.

The EcoBoost is a winner here.  It accelerates strongly whenever asked.  I had no opportunity to evaluate the fuel economy, but even if it results in no tangible gain there, the performance alone makes it worth the price of admission.  I would love to see an EcoBoost four-banger in the upcoming Fiesta or the 2011 Focus.

The final entrée was a 2010 Audi A4 with a 2.0 liter direct-injected turbo-charged engine and a nice six-speed manual.  The driver before me had smoked the clutch, so the distinct scent of roasted clutch wafted through the air as I entered the car.  The clutch engaged a little high, but otherwise the engagement was superb.  Notably, it seemed no louder than the diesels.  The Audi accelerated much stronger than the diesels did and, not surprisingly, much faster than my 2.0 liter 2001 Focus.  The EPA says it returns 22 MPG city and 30 MPG highway, which similar to my Focus.  In this case, the direct injection model with equal displacement gets about the same fuel economy but much, much better performance.  Based on this not-at-all scientific comparison, DI turbos get a thumbs up from me.

In tomorrow’s installment, we cover changes that can be made to a vehicle’s electrical system to improve fuel efficiency, including driving impressions of vehicles with these technologies applied to them.

COPYRIGHT Autosavant – All Rights Reserved

Author: J.S. Smith

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  1. Doesn’t it make you wonder how much sooner we would have this technology if the world’s largest car market had not had some of the world’s cheapest gasoline prices?

  2. too bad bosch doen’t make battries, electric cars are coming

  3. Way too much potential in the ICE yet for a lot less money than simply resorting only to batteries.

    high pressure direct injection and twin turbos on both gas and diesel engines in their current form will make a big difference in the short term.

    Alternative cycle IC engines (like the Scuderia engine) have big potential as do more sophisticated and targeted injections systems and perhaps even fuel catalyst systems will help get more from less and provide the necessary timing and financial buffer and flexibility that many future electric vehicle applications will require to be practical.

  4. Yes, ICE still has enormous potential. But eventually oil will become scarce and there are always emissions problems. At any rate, it will be with us for quite some time. At least technology will allow for high-performance cars that manage to be fuel efficient, but in the short term, I’d wager that cheap performance will be hit hard.

  5. Electric cars still need a powerplant somewhere that belches out toxic emissions in order to get the electricity to charge their batteries.

    Until a LOT of electricity can be generated using the sun, wind, water, and yes, nuclear, all we’re doing is simply moving the emissions problem.

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