2008 Jetta TDI sighted!!! (pics)

[jackbombay]

I used to think that way, but the higher compression cannot overcome the lesser energy content in ethanol.

A vehicle set up to run only E85 could run something probably like 11 or 12 to 1 compression, which would help, but not fully compensate the loss.

Per BTU of fuel consumed, not per gallon, a higher compression engine will be more efficient, ethanol has a high octane rating enabling higher compression thus more efficiency than a gas engine on BTU basis.

 

[fase2000TDI]

Ethanol does NOT have to be made from corn. Hydrogen does NOT have to be made from fossil fuels. The narrow-minded, nearsightedness of some people are absolutely astounding. Look beyond the straw-hole binoculars please.

deedeedee, 75% of electricity comes from fossile fuel. to create hydrogen, you need electricity. deedeedee durpity durp

ethanol still has less energy deedeedeee and it's not anywhere near widely available deedeedeee so most likely 95% of those buying flex fuel vehicles will burn regular gasoline deedeee durp dumbbum

 

[cptmox]

Per BTU of fuel consumed, not per gallon, a higher compression engine will be more efficient, ethanol has a high octane rating enabling higher compression thus more efficiency than a gas engine on BTU basis.

Yes and no.

http://en.wikipedia.org/wiki/Ethanol_fuel

"Some researchers are working to increase fuel efficiency by optimizing engines for ethanol-based fuels. Ethanol's higher octane allows an increase of an engine's compression ratio for increased thermal efficiency [1]. In one study, complex engine controls and increased exhaust gas recirculation allowed a compression ratio of 19.5 with fuels ranging from neat ethanol to E50. Thermal efficiency up to approximately that for a diesel was achieved. [17]. This would result in the mpg of a dedicated ethanol vehicle to be about the same as one burning gasoline. There are currently no commercially-available vehicles that make significant use of ethanol-optimizing technologies, but this may change in the future."

Your right. IF you jack the compression up to 19.5:1. In a gas engine.

 

[bhtooefr]

Turbocharged engines are really the way to go. If I were really serious about ethanol, I'd fix up my Civic, and then slap one of 20 zillion D15B2 turbo kits on.

 

[GoFaster]

Keep in mind that if you optimize an engine to run on ethanol (very high compression, etc) then it can no longer be a flex-fuel vehicle; it becomes essentially dedicated to using ethanol or very high ethanol blends. Right now, it's not practical to take it to that extent.

 

[bhtooefr]

Well, the best way to do it is a turbocharged engine, and then decrease the boost for RUG.

 

[rotarykid]

Well, the best way to do it is a turbocharged engine, and then decrease the boost for RUG.

Just slapping a turbo on an engine not designed to handle the extra stress & heat generated by the boost is a quick path to destruction . Melted pistons , bent rods , blown head gaskets , broken crankshafts , .......ect , if you are paying attention you get the picture . If not happy motoring , for a very short time then Booooooooom !!!!!!!!!!

 

[blacka5]

Per BTU of fuel consumed, not per gallon, a higher compression engine will be more efficient, ethanol has a high octane rating enabling higher compression thus more efficiency than a gas engine on BTU basis.

Well, that's fine, except that you're still consuming more fuel -- you haven't dealt with the fewer BTU per gallon.

BTW, you can do even better with gas, just use 105 or higher octane and optimize to that. That's not generally available as that's too expensive, but so too would be ethanol without the subsidy.

BTW^2, with marginally positive (at best) EROEIs, that 85% ethanol has a lot of fossil fuel in it.

 

[jackbombay]

This would result in the mpg of a dedicated ethanol vehicle to be about the same as one burning gasoline.

Ethanol has fewer btu's per gallon so it is notably more efficient at that point. Measuring efficiency per gallon of fuels that have different btu contents is irrelevant. You don't have to go anywhere near 19.5 to 1 for ethanol to be more efficient than gas on a btu/per work done basis, an increase in compression of .1 would make the etahanol powered engine more efficient than a gasser that didn't have the additional 1/10 of a point of compression. You do however have to jack the compression way up to get the E powered car to go as far on a gallon as the comprable gas engined vehicle would go ona gallon of gas [/off topic]


I'm really looking forward to checking out the CR TDIs when the y get here!

 

[casey_tdi97]

To avoid the brewing ethanol/flex debate, it looks nice in the pics. Maybe I will have to finally let go of my 97 Jetta in/on about 2010. I think the added HP and torque that comes with the larger displacement and technology will accelerate (no pun) VW diesel biased lovers (like myself) well into the future.
Casey.

 

[drshaws]

MPG Quotes! From VAG!

...
Looks like a win-win but did they offer any MPG ratings for the 2.0 CRD?

Of all the days where I'd actually want a cell-phone camera...and tape recorder.

I swung by Altwheels after work. Chatted with a VW PR guy - who quoted 60 highway/40 city MPG! Good stuff.

How do I know they weren't pulling my chain? I look around, and there are some other folks there with a keen interest. PR guy says - "You came at a good time - do you know who's here?" - It was:

1) A VW bigwig of some nature (he wore a bow tie - is that a bad assumption to make?)
2) The 2008 Jetta TDI prototype lead engineer (Er war vom Deutschland, ja).
3 + 4) Tom and Ray Magliozzi, aka Click and Clack from Car Talk.

Yes - the Car Talk guys. Phenomenal. They were impressed. Heard them chatting about the V10 TDI Touarag. Heard the VW guys mention the 60/40 mileage. Heard them joking about the EPA's 'real-world' MPG ratings:
Ray - "No one drives 44 MPH - except for my brother!"
Tom - "My car only goes 44 MPH!"

VW assured them it was legit, real-world 60/40. Woohoo!

Man-oh-man. If I didn't love my dogs so much as to have to catch the 4:30 commuter rail home, I could've stood there for hours.

I also got a VW marketing bit on biodiesel - some kind of cheery/hippie-ish wheel of biodiesel info. Nothing too exciting - only concrete data was the support for B5. I'll take some pics of that shortly and get them posted.

Ahh...pics. Sorry - quality was not so great, as I was in a hurry and don't have a scanner at home.

Enjoy!

Jonathan

PS - extra tidbit - VW PR guy mentioned A5 Jetta Wagons rolling out at the spring NY Autoshow perhaps...(don't know if that news has been around or not yet)

 

[unixgolf]

It looks very promissing, if only they could add the 4 motion to the option list

 

[lawallac]

Instead of having these flexifuel vehicles why not have near 100% ethanol? Then we could take full advantage(?) of what the corn/switchgrass whatever has to offer. Is that not the logical next step and wouldn't it be nice to go to the fuel station and have to choose between beans or corn rather than D2 or RUG.

 

[bhtooefr]

lawallac: The issue with an E100-only (or even E85-only) car is that there's no ethanol infrastructure.

And who's gonna buy a car that they can't fill up just anywhere? Even diesels have that problem, and about 40% of stations have diesel!

 

[jackbombay]

60 highway!? I wonder why the city MPG is so comparatively low?

 

[lawallac]

lawallac: The issue with an E100-only (or even E85-only) car is that there's no ethanol infrastructure.

And who's gonna buy a car that they can't fill up just anywhere? Even diesels have that problem, and about 40% of stations have diesel!

That's what i'm saying. You phase out RUG vehicles to only flexifuel vehicles then eventually start offering E100. As long as the current fleet only lasts so long then all will be good to go.

 

[rotarykid]

That's what i'm saying. You phase out RUG vehicles to only flexifuel vehicles then eventually start offering E100. As long as the current fleet only lasts so long then all will be good to go.

In cold climates E100 doesn't work well to start an engine , that is why we have the 15 % stuff .

 

[lawallac]

In cold climates E100 doesn't work well to start an engine , that is why we have the 15 % stuff .

Hmmm...Glowplugs for every one

 

[TDIMeister]

It is always interesting to read posts by these VW biased owners that believe there is no better "vehicle" than a diesel based VW.
Some of the "efficiency" obsessed VW worshipers do not want to give a credit to any other auto maker or model other than the VW TDi. Why is that?

I thought the point behind alternative ways of propelling our cars it to find what ever alternate source to eliminate Arab oil from our gas stations supply chain. And ANY auto manufacturer that promotes this strategy should be awarded for its push towards renewable or at least domestically produced fuel.

Here, here. You took the words right out of my mouth.

 

[Txst]

Because I bet that Avalanche can burn through corn ethanol like a fat man through Krispy Kremes, and THAT seems very counterproductive to me. Self sufficiency starts with conservation, and that Avalanche and others like it are an oxymoron.

Beasts like that make me ashamed to be American.

Not too ashamed to enjoy the freedoms that we have though huh? Not too many places in the world as free and as blessed as America! Comments like that prove how seriously spoiled and unthankful this nation is!!! That makes me much more ashamed than some vehicle!!!

On the Jetta: Great news, it should be a sweet ride. I'm guessing 52 MPG highway because of the 6th gear, maybe only 34 city.

 

[montge]

Would love to see this in an Audi or a Passat

 

[dieselgeezer]

The last time I looked into the economics of the issue, ethanol production from corn used almost as much, maybe more energy than the energy value of the ethanol that was produced. So, we use imported diesel or gasoline to produce the corn and imported natural gas to distill it. Other than supporting the price of corn, where does anyone but the grower come out ahead?

 

[njkayaker]

I swung by Altwheels after work. Chatted with a VW PR guy - who quoted 60 highway/40 city MPG! Good stuff.

The current Jetta is 42mpg highway. It seems unlikely that the 2008 would get close to 50% better mpg. I'd say we still don't know.

 

[dieseldorf]

I'd refer to the fuel economy number for the Euro equivalent car...that would at least provide some insight.

 

[drshaws]

I'd refer to the fuel economy number for the Euro equivalent car...that would at least provide some insight.

Well, at http://www.vw.co.uk/new_cars/jetta/engines# when you choose the 140 PS/6 spd, you get: (yes, I know those are imperial gallons).
Pferdestärken* 140
Engine cubic capacity 1968
Fuel Consumption
Urban 38.7mpg - 7.3l/100km
Extra-urban 57.6mpg - 4.9l/100km
Combined 48.7mpg - 5.8l/100km
Engine emissions 157g/km
Engine noise levels 74.0dB
Engine maximum Speed** 128mph - 207km/h
Engine acceleration 0-62mph 9.7secs
Maximum output PS 140
at RPM 4000
Maximum torque 236 lbs.ft / 320 Nm
at RPM 1750
Insurance group rating 9

 

[dieselgeezer]

Speaking to the issue of hauling big loads, In 1966, I pulled a 2000 pound U-Haul trailer with all my worldly goods therein 350 miles over the Cumberland Mountains with an unmodified 1.1 liter 65HP Opel Kadet that gave me 38 MPG highway (without the trailer). It was a dumb thing to do and I had to stop and tighten the bumper bolts a couple of times but it shows that you don't need 2.5 tons of truck and a 6 liter engine to tow a trailer once in a while. Experience with that little gasser also leads me to believe that I don't need a ton and a half of Volkswagon to commute to work every morning, even though I currently get 47 MPG. My 06 Jetta TDI should do just fine with about 700 fewer pounds and get much better fuel mileage.

 

[TDIDerek]

Well, the best way to do it is a turbocharged engine, and then decrease the boost for RUG.

In my experience when you add the turbo it starts eatin up fuel. My 91 Talon AWD drinks fuel like water, seems like even if im not getting into the boost.

 

[bhtooefr]

Well, that's partially because you have a decent-sized engine.

Something like a 1 liter engine on low boost would give you the power of a 1.5L NA engine, but you still have the turbo flexibility.

Also, the VW 1.8T isn't at all bad on fuel.

 

[TDIDerek]

The first time I saw a TDI was my mother in-laws Jetta. I swore up and down that it wasnt turbo because it doesnt howl like my turbo on my talon does. I sorta migrated to them because of the gas mileage and the fact that theyre turbo - everything is better with turbo

 

[jackbombay]

Extra-urban 57.6mpg - 4.9l/100km

Which is 48 MPG for a US gallon, my 03' wagon at 50 MPG is Still the undisputed king of the hill