dvs_dave

For sure the high torque makes for relaxed performance and makes the car feel fast as it just goes without downshifting and having to rev. However 240hp can only do so much, regardless of torque and 8 speeds. 350hp can do a lot more. Always has, always will, especially in a slightly lighter vehicle.

Anyway, my point is I don't think the U.S. Diesel options can be reasonably compared to the gas options as they're too underpowered and restricted compared the Euro diesel options; ultimately leading to disappointment. Yes, its better, faster and smoother than you expect, but when you were expecting a truck engine it's not difficult to impress.

Trust me don't believe the hype. The diesel options in the U.S. just don't make any sense outside of novelty value and gas mileage (on a $100k car, an oxymoron if ever there was one ) as on all other fronts they just don't perform as well as the gas engines. I'm talking from real world experience here being a Brit coming from the world of super expensive fuel and diesels being the default choice.

mishar

That's the whole point in day to day driving. Of course 100 HP makes difference. But you have to downshift and rev it up like crazy, which is way less smooth than any Diesel. Diesel fuel is more expensive than gas in US, but that can and will change. Again, fuel economy of a $100K car is irrelevant. So is fuel price difference.

Here is power/torque of V8 TDI compaired to V8 FSI. Not the same as V6 but on the same line.

dvs_dave

I know all about torque curves. However you only really have about a 2k rpm rev range where it's any good. Same with the V6 TDI so you need that 8 speed box.

U.S. V6 TDI is ultimately underpowered for the size of car. Only it doesn't feel it day to day as the engine is operating at its peak output point most of the time whilst at cruising around speeds. Great if all you care about is getting from A to B, but it quickly gets very dull when you realize it doesn't have anything else to give other than more noise.

I speak from first hand experience from years of driving modern diesels all over Europe. Gas engines are ultimately much nicer. Bolt on the turbos and other complications that TDIs need to match NA gas, and there's even less of a contest.

Diesel passenger cars are an over priced novelty stateside, and in Europe with the onset of super clean modern turbo high mpg gas engines, diesels are becoming less and less relevant. Until gas prices get way way higher diesel passenger cars will remain a curiosity at most in the U.S. And by that time electric power will have taken over anyway.

mishar

If you check those curves you will see that TDI has more torque and power throughout it's rpm range, which is where 99% of driving happens.

Flat and high torque curve requires less gears than high rpm peak ones. Eight gears are there for smoothness and prestige. It would work just fine with three gears.

Exactly! That's how luxury car should work.

That bothers only high rpm junkies. But two tons and bulky body should bother them even more.

Same here. As a matter of fact I am driving one of those right now. Speaking about modern, I have yet to try that BMW 3 liter 385 HP 3 turbo Diesel.

chokboywonda

'Great way to invalidate the power train warranty though and it's still way down on power. No amount of chip tuning will add over 100hp. A cursory glance of the net shows a solid performance difference too.
240hp vs 350hp
6.3s vs 5.9s 0-60
15s vs 14s for the 1/4'

I know nothing about US diesels etc. but what I do know is when a BMW M3 is at the lights with me they get a hell of a surprise Lol
As for the noise if I was to debadge my car only the average person would not know it was a diesel. where did you get the figure of 240hp? I thought the D4 was meant to have more hp that the D3?

chokboywonda

VCDS question
How do I do a 0-60 test in VCDS?
i have time tomorrow so I will try it and post the times

EHLO

For me the primary benefit of diesel would be less frequent stops for fill up, and I actually prefer not having to rev the engine.
Even with diesel priced higher than gas, there is a cost savings if you keep the car long enough to amortize against the option cost.
Diesel is cheaper to produce than gas, but until there is a tipping point that forces the refineries to reallocate production, it will stay more expensive.
I'm hoping the D5 SWB will be available with a diesel.

dvs_dave

Not sure where you're located but the only TDI version available in the U.S. is the base V6 with 240hp. Right there on audiusa.com.

And yes modern diesels are quiet and smooth and very acceptable. But they don't rival equivalent gas engines on that front, or sound anywhere near as good. Compression ignition makes that virtually impossible.

chokboywonda

Ahh ok. I'm in the UK
My TDI is as follows:

Engine Size 4134 cc, Cylinders 8,
0-60 mph 5.9 secs, Top Speed 155 mph
Power Output 321 bhp, Torque 650 Nm 479 lb-ft

(After remap I think it is 370 but I'll have to look and check)

The D4 is:
Engine Size 4134 cc, Cylinders 8
0-60 mph 5.4 secs, Top Speed 155 mph
Power Output 345 bhp, Torque 800 Nm 590 lb-ft

As for the sounding good that's really not my cup of tea as I am more into hearing the music in my car rather than engine. My car is dynamtted also.

So the solution is to come to the UK I reckon mate

dvs_dave

Gotcha....V8 TDI is a whole different story and is directly comparable to the NA V8 gas. If the V8 TDI were available in the US then I would rather have one of those than the NA V8 gas as they are for sure faster, and get better mpg.

What I don't get is why folk think that the puny 240hp V6 TDI is comparable to the 350 hp V8 NA...."because moar torque!" It's just not. I think they've been suckered in by the Audi USA marketing, tenuous Le Mans links, and the fact it's a new and shiny engine option never previously available in the US.

Another ridiculous part of it is that the V6 TDI is the entry level economy option in Europe, as it should be. In the US though it's not the base engine, that would be the almost 100hp more powerful, considerably quicker, not much less frugal 3.0T (chip these to 450-500hp easy!). Audi are literally laughing in everyone's faces by charging more in the US for the lowest and cheapest engine spec they do and suckers are still happy to pay a premium for the novelty value.....completely nuts!

With regards me coming to the UK, I've come the other way. I'm a Brit living in the US and much prefer having large NA gas engines and cheap gas over essentially being forced into having to drive a diesel due to the market conditions. Big NA gas engines are just not a viable option in any way shape or form due to running costs in Europe which made me sad.