Efficiency Experts | Chevrolet Volt vs. VW Beetle TDI

By J.G. Pasterjak
Aug 28, 2022 | Chevrolet, VW, beetle, tdi, Volt, Efficiency | Posted in News and Notes | From the June 2013 issue | Never miss an article

Photography by J.G. Pasterjak

[Editor's note: This article originally appeared in the June 2013 issue of Grassroots Motorsports, before the "Dieselgate" scandal and when both the Volt and Beetle TDI were new cars on the market.]

It’s probably time to admit it: The future may not be as exciting as we’ve been led to believe. We can all certainly be thankful that August 4, 1997, came and went without Skynet becoming self-aware, though we did eventually get Facebook, which may have actually been worse. And in less than two years, Marty McFly and Doc Brown are scheduled to return to a Hill Valley complete with hoverboards, “Jaws 19” playing in holographic 3-D, and self-fitting clothes in department store window displays. None of the aforementioned is likely to exist by then. The giant trucks of horse crap, however, probably will.

They didn’t get it all wrong. Although “The Running Man,” a fictional reality game show in which people are hunted and killed for sport, isn’t supposed to premiere for four more years, there are several reality game shows currently being broadcast where simply being one of the horrible humans involved is a far worse fate than death.

What does all this mean to us, the auto enthusiast populace? We’re a paranoid crowd. Each advance in technology brings a new cry from the masses that our fun is being quashed. But if we look back to recent automotive history, we can see that nearly every technological advance first believed to signal the end of performance and fun—digital engine management, ABS, fuel injection, traction control—has also produced a high-performance analogue. Cars are now faster, better-handling and safer than ever, and we haven’t lost much—if any—of the tunability we crave. In some cases, our wrenches have been replaced by laptops, but the sentiment remains the same.

Future Shock

This brings us to our latest project car series. We’ll warn you in advance: This one is a bit of a departure, even for us. And that’s because the mission is different—it’s more of a thought exercise. We’d like to determine what impact the next big wave of technology will have on our enjoyment of cars. Specifically, is the move toward alternative propulsion a signal of the end of driving fun?

For this task, we’ve chosen a couple candidates that sit a bit outside what you’re used to seeing in these pages. Representing the more traditional approach to alternative propulsion is the Volkswagen Beetle TDI. Powered by a 2.0-liter, direct-injected and turbocharged diesel powerplant, the Beetle TDI is the latest in a long and respected series of diesel-powered VWs. The current TDI powerplant is an evolution of the engine that has won numerous International Engine of the Year awards and a cousin (albeit distant) of the Le Mans-winning Audi LMP powerplant. 

VW built their reputaion on out-of-the-box thinking, and today’s Beetle TDI lives up to those grand traditions. Pairing an efficient, high-tech diesel powerplant with a sporty, dynamic chassis produces a car that’s more fun and satisfying to drive than it has any right to be. The smiles continue at the fuel pumps as well.

With 18.5:1 compression and a boost gauge that reads to 35 psi, the modern TDI moves a lot of air from Point A to Point B, but it does so with remarkably little fuel. As we’re finding out, the TDI experience is more active than we gave it credit.

What does that mean? Put simply, the performance of the TDI is in direct proportion to your skill in driving it. If you hop in and drive off as though you’re in command of a regular, gas-powered automobile, the results will be a bit underwhelming.

But once you become attuned to the engine’s distinct characteristics—like that 236-ft.-lb. mountain of torque it produces from as low as 1800 rpm to around 2500 rpm—you start to see the beauty.

Can We Torque?

Why are diesel engines known for their torque? Billy Squier summed up the reason in his 1981 arena rock hit “The Stroke”: The stroke’s the word. 

Remember when we told you the TDI has an 18.5:1 compression ratio? You can only get there by moving the pistons a looooong way, and you can only move the pistons that distance with long connecting rods attached to a crankshaft with highly offset journals. In other words, you need a long stroke. The torque is created through the simple mechanical advantage of the longer lever arm, which is formed by those highly offset crank journals accommodating those long rods. While that long stroke makes for an engine that doesn’t like to wind too high—anything past 4500 rpm is just making noise—it makes for a wonderfully torquey engine that begs to be driven properly to produce its full rewards.

Once you learn how that torque curve feels—how it doesn’t come on right from idle, but needs a little momentum to get things moving, then drops off at around 3500 rpm—you’ll realize that the Beetle TDI is not merely the diesel-sipping economizer you once thought it was. Keep it in a gear lower than you’re accustomed, and you’ll notice that you can squirt through holes in traffic like you’re driving an S2000, just at a different end of the rev range. We’re so used to horsepower that we forget how to drive with torque—and how fun that can be.

And already we’ve used the word “fun” to describe a car in this story. Driven properly, the TDI is just that.

Electric Boogaloo

This brings us to the Volt

No, don’t panic. We’re not going to suddenly start running stories about how you can make pants out of hemp and use car wax to maintain your dreadlocks. If there’s one thing we can all agree on, it’s that hippies are annoying. Unfortunately, cars like the Volt have gotten an unfair rap merely for being associated with certain highly polarizing characters.

Being green comes naturally to some, but the rest of us have to work at it. For the Chevy Volt, that means throwing several NASAs worth of technology into a single chassis, all with the goal of operating as efficiently as possible without compromising on modern creature comforts and conveniences. That technology comes at a price, though. The Volt’s electric motors and battery packs add mass, and at 3800 pounds, it will never be mistaken for a Lotus Elise.

However, that’s maybe what attracted us to the Volt in the first place. We’d been contemplating a hybrid project for a while, but around this time last year we had a loaner Volt from GM’s press fleet. On one of our morning commutes in the Volt, a kind citizen in the parking lot of a Burger King informed us—completely unsolicited, mind you—that “Obama only built the Volt to appease the United Auto Workers goons who were threatening to go public on his real birth records.”

Now, we profess no real political leanings, but it was clear from that statement that the Volt was a lightning rod for opinion. We needed to know more.

So our acquisition of the Volt served a few purposes. First, we wanted to separate myth from reality as much as possible to discover what this car was really all about. And second, we wanted to examine what is arguably today’s most high-tech mass-produced automobile to see if it heralds a buzzkill for enthusiasts of the future.


By now, most of the misinformation that was circulating regarding the Volt has been cleared up. For example, we now know the following:

  1. Volt engineers are not actively trying to burn you alive. During NHTSA impact and rollover testing, a Volt battery assembly was compromised. It was then left upside down (not part of the testing protocols) and caught fire two weeks later. If you aren’t extricated from your vehicle within two weeks of a crash, fire will be the least of your problems. Unfortunately, this data was inserted into a sensationalistic news culture that keyed on the words “Volt” and “fire.” The rest is history.
  2. Each $42,000 Volt does not lose over $80,000 for GM. Again, news outlets looking for a catchy one-liner divided the total development cost of the Volt by the number of units sold at the time that particular story was written. It’s the same thing as saying the first two hamburgers to come off your brand-new $400 grill cost $200 each. As Volt sales continue, the incremental unit costs of each car will decrease. And even if the Volt itself never “turns a profit,” you can’t take away the advances in technology that GM gained because of the program. 
  3. The Volt is not worse for the environment than a Hummer because it uses power from coal-fired plants and batteries made of cancer sauce and embryonic stem cells. First off, this line of thinking completely ignores the economies of scale that come into play when those coal-fired plants produce electricity that will be used in a Volt. You know that they don’t just fire up those plants to charge a single Volt, right? 

It also ignores the fact that less than half the electricity in the U.S. is provided by coal plants (many of which are clean coal plants), and that number is shrinking. According to our Florida power company, our Volt gets 80 percent of its power from natural gas-powered plants, about 15 percent from nuclear plants, and 5 percent from other sources. This means that we aren’t contributing to additional mercury in the air from coal plants, but we probably are setting some hillbilly’s tap water on fire from fracking. The bottom line is that any transfer of a base resource into usable energy has some environmental impact. The key is finding technologies that minimize that impact.

Oh, and as for the batteries and their materials, they’re 100-percent recyclable and highly sought after on the secondary market. The chance that you’ll ever live in a dystopian future world where used hybrid batteries litter the streets is virtually nil.

Everyone’s a Critic

Our initial experience with the Volt was positive—no buyer’s remorse, anyway—but we wanted to explore some of the criticism. So we called up Fox News and asked to have a chat with one of their network’s most outspoken Volt critics, Fox News’s “The Five” co-host Eric Bolling. Last year, GM loaned Bolling a Volt press car, and his televised response—and the comments of his co-hosts—made him seem less than impressed. Much of the commentary focused on the fact that the primary drive battery ran out of juice in the Lincoln Tunnel. 

“I’d rather roller-skate backwards through the Lincoln Tunnel than break down,” remarked one of the co-hosts. No mention was given to the fact that once the primary drive battery is depleted, the Volt continues on powered by the gasoline engine in a more “traditional hybrid” mode.

We thought we’d pretend we were real journalists and give Mr. Bolling the chance to clarify his position on the Volt. In reality, he’s a guy with some legitimate criticism of an intriguing but imperfect car. “It’s got some very interesting technology, but I just don’t think it was quite ready for prime time,” he told us, summing up his experience. “I followed all [GM’s] guidelines and got about 25 miles to a full charge before it switched over [to gas mode]. That’s way below the 40 to 45 we were led to believe.”

And he’s right. True, during the summer months, our Volt routinely made it 42 to 45 miles on a full charge with the air conditioning going. But as the ambient temperatures dropped, so did our battery range. In December, we averaged about 35 miles per charge on Florida’s flat and smooth roads. A 25-mile range commuting into a frozen New York City is completely believable. 

Bolling also wasn’t fond of the fact that the Volt was released into today’s social and political climate. “I’m uneasy with a company releasing such a risky car after having taken so much taxpayer money that we never really got to approve. Again, the technology is neat, but it’s also unfamiliar. I had to plug it in once in the rain. That caused a few uneasy moments holding that high-voltage connector in a storm.” Again, more valid points. Sometimes the driving public can only take so much newness at once.

But even a harsh critic like Bolling has a soft spot for progress: “It’s really a decent car, and I think future models will improve on the technology, but I just don’t think this version is there yet. I think for now, the more traditional hybrid is where the attention should be focused.”

So far, we’ve sort of come to the conclusion that the Volt isn’t the future, but it’s certainly a bridge to the future. Now we just need to determine whether that future will suck or not.

Initial Thoughts and Future Plans

We’ll cut right to the chase: The Beetle TDI is orders of magnitude more fun to drive than the Volt when measured by traditional dynamic means. The VW, despite its diesel-sipping engine, is still a driver’s car. And, of course, it should be. After all, it shares a common chassis with the Golf, Jetta, and Audi TT, all undeniable driving machines.

The Volt, on the other hand, has more pedestrian DNA. It shares a chassis with the Cruze, which no one will ever accuse of being sporty. What GM has done, though, is rip out the guts of the Cobalt and replace it with a space shuttle, several HAL9000s and about 20 iPhones. Enjoying a Volt means retuning your definition of how you enjoy cars. While the car is decent dynamically—certainly no match for the VW—its real appeal is to the technophile. 

The tuner garage of the future could look decidedly different. Powertrains are changing, but gearheads aren’t. Whatever the car companies build, we will find a way to make it better.

As we’re finding, the Volt is almost creating a new breed of car enthusiast: folks who are enthused about an amazing machine that just happens to be a car. One of the hardcores on the gm-volt.com message board—a gentleman who installed a solar-powered charging station for his Volt and has run it entirely on solar energy since he’s had it—summed up the origins of his enthusiasm thusly: “My father had the air filter off of his 1970 Corvette once and he gave it some gas. I could see all that gas pouring into the carburetor, and it was an image that stuck with me. The photons on the roof replacing hydrocarbons in the cylinders is completely liberating.” He’s enjoying his car; he’s just doing it in a way that isn’t measured in lap times or lateral g-loads.

But if you do want to use those things as your yardstick, may we suggest the Beetle TDI? Seriously. It redefines how dynamically exciting an efficiency-oriented car can be.

By the Numbers

Before we wrap up this intro to our latest weird project, let’s look at our first metric for evaluating these cars: operating costs.

This is a difficult comparison because the Volt’s costs are complicated to calculate. However, here are some numbers to consider for both cars when it comes to efficiency:

From the VW Beetle TDI, we’ve seen highway mileage as high as 46 miles per gallon and mixed driving mileage as high as 39. These sound like awesome numbers—until you visit the pumps. In Florida, diesel currently runs about 30 cents more per gallon than premium fuel ($4.19 versus $3.89 per gallon). This means it costs about 9.1 cents per mile to fuel the VW on the highway. That same 9.1 cents would also take a gas car a mile, assuming that gas car was getting about 35 miles per gallon. 

On fuel cost alone, the choice between the Beetle TDI and a traditional gas car is not as clear as it once seemed. So we’ll throw in a couple more variables and wild-ass assumptions. First, a diesel car getting 46 miles per gallon is likely to be of a higher trim and equipment level than a gas car getting 35 miles per gallon. Yes, there are several “nice” cars (Mazda’s Skyactiv-powered lineup comes to mind) getting great highway mileage, but in general, getting more than 30 miles per gallon these days requires shopping in the bargain basement of your dealer’s lot. Also, diesel cars will generally run for more miles and hold their value better than their gas counterparts. Again, this is anecdotal evidence, but it’s well-founded anecdotal evidence.

Now let’s do some math with the Volt and really confuse things. A full charge of the Volt takes about 9.7 kWh (about the same energy consumed in cooking a frozen pizza) and can propel the Volt roughly 40 miles. In Palm Coast, Florida, those 9.7 kWh will cost you about 73 cents during off-peak hours (from about 9 p.m. to 7 a.m.) and about $1.20 during peak hours. For the sake of argument, let’s say it costs roughly a buck to fill up your Volt’s battery. That means each mile costs roughly 2.5 cents while you’re operating on the battery. Now, considering that the average commute is 15 miles and over 80 percent of the driving public drives less than 40 miles per day, those are pretty intriguing numbers.

And once the battery is depleted, what then? Well, the Volt shifts over to a more traditional hybrid mode, motivated by the 1.3-liter gas generator and the electric motor. Unlike more traditional hybrids that use a CVT or a geared transmission, the Volt uses a series of planetary gears and witchcraft to channel power from the electric motors and gas motor to the wheels. This allows the gas motor to operate in a very narrow rev range where it’s most efficient. The result is roughly 40 miles per gallon on the highway, or 42 miles per gallon around town and in mixed driving.

What you begin to realize is that the Volt is more of a specialized tool. If its capabilities lie within the scope of your needs—which, for many drivers, it will—then it’s an extremely efficient tool. If not, it’s downright mortal.

Oh, and did we mention that it costs $42,000? Of course, you’re entitled to a $7500 tax credit, but it’s still a stiff chunk of change.

The bottom line on both cars is that they’re naturally highly efficient, and each brings its own brand of fun to the table.

Now for the cool part: Can we make them more fun?

In upcoming issues, we’ll explore the ins and outs of trying to add performance to cars that weren’t really intended to have performance added to them. We already have a set of KW coil-overs specced for the Volt, and it’s our intention to run the VW at our Ultimate Track Car Challenge at Virginia International Raceway in July. Are we tilting at windmills? Are those windmills hooked to generators? We’ll find out.

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Colin Wood
Colin Wood Associate Editor
6/2/22 4:56 p.m.

Just got this article on site because a thread about it got revived early today:

Essay on Volt/TDI Article

John Welsh
John Welsh Mod Squad
6/2/22 6:29 p.m.

I drove that TDI Beetle during touring laps of The Mitty, back in the day!  It was torquey and really not that underpowered. 

frenchyd GRM+ Memberand MegaDork
6/3/22 11:06 a.m.

In reply to Colin Wood :

It's fun to see how far the average person has come regarding alternative power.  
 From EV's are for Hippies to EV's don't  have required range, to EV's are too expensive.    
  Since the New Chevy Bolt is $25,xxx  that make electricity penny cheap. 

Tig New Reader
8/28/22 1:43 p.m.

As if Big Brother government of the future will ever allow a "tuner garage of the future" 

There will be no 'tuners' permitted and the aftermarket industry will slowly die with ICE 


Pete. (l33t FS)
Pete. (l33t FS) GRM+ Memberand MegaDork
8/28/22 2:16 p.m.

In reply to Tig :

Tuners are already not permitted and never were.


That said, you bring up an interesting point.  EVs are exempt from Clean Air Act provisions.

RustBeltSherpa Reader
8/28/22 2:18 p.m.
Tig said:

As if Big Brother government of the future will ever allow a "tuner garage of the future" 

There will be no 'tuners' permitted and the aftermarket industry will slowly die with ICE 


Check out Alan Cocconi of AC Propulsion. He was creating tire-smoking CRX EV conver-sions in the early 1990s. Tesla borrowed heavily on Cocconi's EV engineering expertise. Perhaps Tesla wouldn't even be a thing today without that expertise.

MadScientistMatt UltimaDork
8/28/22 4:26 p.m.
frenchyd said:

In reply to Colin Wood :

It's fun to see how far the average person has come regarding alternative power.  
 From EV's are for Hippies to EV's don't  have required range, to EV's are too expensive.    
  Since the New Chevy Bolt is $25,xxx  that make electricity penny cheap. 

Although a lot of that is due to how far EVs themselves have come. In the 1990s, an EV might have a 40 mile range with a ton (literally) of lead acid batteries and would likely be a homebrew creation. Mainstream auto makers had a few experimental test mules that you couldn't buy, and any EV for sale would be a conversion put together by an outfit closer to an organized hobby than a business. They were for hippies back then, and a couple niche uses.

And it's going to be a while before $10,000 buys a reasonably serviceable used EV. Though if the battery packs can hold up, probably only a matter of time.

03Panther UberDork
8/29/22 2:54 a.m.

In reply to MadScientistMatt :

As long as that magic emissions free stuff keeps getting pumped through the walls, he is right, though. 
Solar will charge your ev all night long, and wind turbines work 24/7/365. 

Apexcarver UltimaDork
8/29/22 3:28 a.m.
Tig said:

As if Big Brother government of the future will ever allow a "tuner garage of the future" 

There will be no 'tuners' permitted and the aftermarket industry will slowly die with ICE 


"That newfangled electronic fuel injection will be the end of tuning, just you wait and see." - some 1980's enthusiasts

No emissions to violate laws with reprogramming the computer to put down more power... Or upgrading battery packs.  Or swapping bigger aftermarket electric motors. Or adding additional motors for awd...


Prices will continue to fall as production expands


Apexcarver UltimaDork
8/29/22 3:34 a.m.
03Panther said:

In reply to MadScientistMatt :

As long as that magic emissions free stuff keeps getting pumped through the walls, he is right, though. 
Solar will charge your ev all night long, and wind turbines work 24/7/365. 

There's a lot of activity recycling battery cells that have lost enough capacity to make them not too useful for evs into stationary power banks to help with this.

Battery only holds about 75% charge, so diminished range no good for the ev? Add it to a bank by the solar station (after due safety testing) and it gets charged all day and powers the grid at night. 

There are also home solutions being done. See Tesla power wall.

03Panther UberDork
8/29/22 4:14 a.m.

I've had an interest in EVs, solar power and other cool stuff since the late '60s. Didn't take a math  genius to figure out I was too poor to play in that world, and still am. I know DIY saves a few bucks over paying full price for stuff. And the whole subject is leaps and bounds ahead of where we were then. 
I also know a lot of the facts that get repeated ain't actually facts. 
Its all an intellectual discussion for me, anyway, as I am a decimal point or two below the target market. 

Apexcarver UltimaDork
8/29/22 5:16 a.m.

In reply to 03Panther :

Price keeps tumbling down as scales of production ramp up. The next 5-10 years, there will be a lot more affordable spares and solutions on the market.

03Panther UberDork
8/29/22 9:18 a.m.

In reply to Apexcarver :

Oh, absolutely. Things have improved. And , other than a natural plateau from time to time, at a logarithmic scale.  
And they now get more output per square ft than they used to. 
But they advertise in square mm, and average household needs are already needed to be measured in square yards. 
If I cut down a lot of trees (won't be happening) and paneled the part of my roof facing correctly, and filled the available yard with panels instead of grass, I could maybe reduce my power bill by 10-20%. Add charging a car to that, and my power is not gonna go to "FREE" as many proponents (including on here - at least you stick to more realistic data!) LOUDLY claim!!!

wish the economical superconductor was here, but wanting it don't make it so. 
Remember: "as soon as we get nuclear plants operating, we won't even need meters at the houses". 

Apexcarver UltimaDork
8/29/22 11:56 a.m.

In reply to 03Panther :

I agree that it wont generate everything, but, if it can take up a significant portion of power requirement and is iterated across the grid...  (10-20% counts as significant)

It just sounds like you are saying "its not worth doing because it doesnt solve the whole problem".  I would disagree with that notion if that is what you are trying to say.  I am not saying "go get solar now" I am saying its a worthwhile consideration.  Yeah, solar doesnt work everywhere or for everything, but it has a place as part of a portfolio approach.


But we digress.  The primary thing is that, yeah, things are changing, but the sky is far from falling. Enthusiasts will overcome and adapt and there are aspects that are downright exciting.  Hell, there are multiple 1,000hp equavilent EV's on the market or coming on in the next few years... 

  1. Tesla Plaid - $130K - 1020hp
  2. Lucid Air - $150K - 1050hp
  3. Faraday FF91 - $TBD - 1050hp

and for comparisons sake...  Corvette Zo6 - 670hp - $106K

Yeah, its in the luxury market, but not per-se supercar deep and its still somewhat emerging tech where prices will be dropping.   Thats the OEMs, when you can order motors on their own on the aftermarket?  I mean, GM has the E-crate thing that puts out something like 700hp.  Yeah, price is high, but thats for now...  It will trend downward.



03Panther UberDork
8/29/22 10:56 p.m.

I agree with the " we digress. "
I will point out I mentioned that your reasonable discussions are not what I am disagreeing with. So you MAY be reading something into my comments that is not there. I AM writing in disagreement  to the commenters that say it will magically fix everything. You have never said that, that I am aware of. 
I have NEVER said alternatives are not worth looking into, trying, or developing. In fact, I often state that I've had a fairly high interest since the late '60s

It just that it's a very popular thing for some people to repeat reteric, with out knowing (or wanting to know) anything but what they heard on the news.
10-20% can be a significant amount, but not in the secinario described in context. 
My face to face conversations are bad enough, but my written comucations are not the best. I only responded to you,to clarify your misinterpretation (my fault, I'm sure) of a generalized statement I made. Not to disagree with anything you have said.

We are not as far apart as you might think!

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