[BMW335iOn18s]

Here's a pic for proof

[WreckerX5d]

I think a few of you forget that (Torque*RPM)/5252=HP.

HP is distance over time (speed, MPH, ect)
Torque is rotational force.

Diesels by nature produce a large amount of torque because the BTU of diesel is so much greater than that of gasoline. They also burn at a slower rate thus limiting their rev range.

All things being equal (vehicle weight, gearing to match RPM, ect), a 300hp car, whether it's gas or diesel, will still accelerate like a 300hp car should.

If technology advances enough to engineer a diesel engine to match the RPM range like a gasoline will, they will be far superior.

We can take my car as an example. If I just increase my RPM to 6000 max (that's only 1000 more), and maintain the same amount of torque of let's say 490 crank (accounting for some loss), the peak HP will increase from 415 @ 4300 to 541 @ 5800. That seems like a pretty good amount, and I'll still maintain my 42mpg on the highway.

Everyone has their own opinion about which they prefer, and rightfully so, but you cannot just discredit a diesel's engine performance based off emotion and nothing more. They do have some disadvantages like the unfiltered smell, and nor do they sound as good as some gas engines will, but I think I can live with that.

[anielsen71]

Originally Posted by Lobb

The big torque numbers for diesels (always quoted in NM because it's a bigger number, rather than lb/ft) was latched onto by the marketing departments of car manufacturers in the early days of flogging diesels as the BHP figures were so puny. Big NM torque means big performance doesn't it? Er no.

Errrhhh no. You Guys (US and UK) are using imperial messuring and use lb/ft.

All the other parts of the modern World has changed to metric mesuring.
Thats why we use NM. No other reason than that.

[123sub]

Diesel in Your own car? No way. Kep that xxxx out of the garage.

[SabineBimmer]

Originally Posted by Lobb

Torque at the crank is meaningless. A diesel has a relatively small operating rev range, so needs tall gearing to cover the necessary road speed in each gear. You need to see the data for torque at the wheels or even better thrust at the wheels to get an idea of performance in each gear.

The big torque numbers for diesels (always quoted in NM because it's a bigger number, rather than lb/ft) was latched onto by the marketing departments of car manufacturers in the early days of flogging diesels as the BHP figures were so puny. Big NM torque means big performance doesn't it? Er no.

Then you've got the other Achilles heel of diesel engines. The weight. All the drive train components need to be stronger (read heavier) to handle that torque.

ACS have answered a question no one had asked (thankfully). Fortunately ACS will remap your b58 I6 petrol engined M140i to 380bhp, for the true BMW experience.

You bring up some excellent points, but in terms of customer perception, would they not feel the difference in torque? Surely, that larger sense of thrust would be worth the price of admission for most. Now granted, the marketing types have their hands in how they advertise those numbers but the engine sells itself once you drive it.

In other words, this car is a win!

[SO17]

For all the diesel naysayers: I drive an Alpina D4 BiTurbo. 345bhp, 527 ft/lb torque AT THE WHEELS ( measured on a Dynojet), 0-60 in 4.4. It even sounds better than the ultimate farting machine.

[N8N]

Originally Posted by Lobb

You're getting confused with the torque numbers again. At the crank they mean nothing. If you overlay the thrust at the wheels of a 335d and a 340i the petrol engine wins every time. It's torque at the WHEELS that's the key. Not the number the marketing men quote you.....

You wouldn't want a big diesel with a manual shift. Dreadful things because of the torque reversal effect off throttle through the drive train. I had a e90 3.0d briefly with the manual transmission.....

Yuk!

I understand that a 335d is not necessarily directly comparable in performance to an E92 335i or a F32 340i... However, what I've seen reported is that the old 335d was far from a slug.

I also am struggling to maintain a 21-22 MPG average, on premium fuel, in my 335i 6M because of the traffic conditions around here. Sure, I can achieve 30 MPG on an open highway, but I never drive on them because they don't exist, at least during the hours that I'm driving on them. I'm always accelerating, braking, occasionally panic stopping or accelerating hard because of idiocy occurring around me. Last time my car was in for service I had a F30 325d and found it to be quite adequate and *significantly* more economical; however, I would think that a 335d would be a little more to my taste just because I like the extra power. But the 1.5-2x improvement in fuel economy using cheaper fuel is kind of a big deal.

What I couldn't abide, and can't abide in any of the loaners I've had, is the completely counterintuitive automatic shifter in modern Bimmers. It reminds me of the fundamentally flawed Chrysler shifters that have gotten such bad press lately after the death of Anton Yelchin. What is so wrong with a standard PRNDL? I don't drive *only* BMWs, I don't like having to commit a long list of special instructions to memory (or better yet, muscle memory) to properly operate a vehicle. The turn signal switch was bad enough, although I have to admit that I like it after getting through the adjustment period. The shifter is really, really bad though and reminds me of the confusion I had when I got my first company car, a column shift Impala, after having driven no automatics whatsoever for decades save for really old project classics that had a "PNDLR" pattern, took me weeks to stop putting it in manual first when intending to back up. This kind of confusion is not only unnecessary and irritating, but can cause incidents.

That, and I just prefer stickshifts. I understand what you're saying about torque reversal, but I haven't experienced it, because I've never had the opportunity to do so, because BMW does not see fit to allow me to try it for myself, so I have no idea if I could deal or not. FWIW I find the N54 to have very mild compression braking; certainly less than I'm used to with e.g. an old high-compression Stude 289/4-speed/3.73:1 combo or even my old 80's FWD VWs (various 1.8 8v and 16v cars)

[W///]

Originally Posted by BMW335iOn18s

I was one of the US BMW enthusiasts who wanted BMW to bring us more diesels.

This is a case of "grass is always greener."

After 1 week with a F11 520d m sport, I can say the diesel is honestly crap, and a N20 528i (which is my mothers car in the US) is leagues better and nearly as efficient.

The 520d only averaged 30 mpg US over 1800 miles. 38 highway 24 city...not better than our 528i. If fact the 520d was insanely laggy and downright SLOW. Only good for slow city driving. The autobahn was borderline painful. I got used to it but we have the cream of the crop in the US with the N20/N55/N63. Smooth, insanely wide power band, efficient, minimal turbo lag and great sound. The diesel had a narrow power band with no power until 2000 rpm, dying off at 3500 rpm in addition to sounding like a baby tractor.

What we need is a F11 535i in the USA!

You got the wrong car IMO. The only diesel I'd really consider are the 6 cylinders. Far more refined, quiet, torquey and less laggy.

When I was in Europe, I had a F11 530d and it was an absolute joy. I'm a big fan of M cars with MT's (got 2 of them, planning to add 1 more), but I would absolutely love to have that rental car I had as a DD. Such a shame we don't get Tourings anymore, they're amazing.

[BMW335iOn18s]

Originally Posted by W///

You got the wrong car IMO. The only diesel I'd really consider are the 6 cylinders. Far more refined, quiet, torquey and less laggy.

When I was in Europe, I had a F11 530d and it was an absolute joy. I'm a big fan of M cars with MT's (got 2 of them, planning to add 1 more), but I would absolutely love to have that rental car I had as a DD. Such a shame we don't get Tourings anymore, they're amazing.

The 6 cylinder diesels aren't even THAT efficient....but maybe you're right. I just think that if I had a choice between a 535d and a 535i, I'd still pick the N55. Especially given that gas is cheaper than diesel for us Americans.

[N8N]

Originally Posted by BMW335iOn18s

The 6 cylinder diesels aren't even THAT efficient....but maybe you're right. I just think that if I had a choice between a 535d and a 535i, I'd still pick the N55. Especially given that gas is cheaper than diesel for us Americans.

Where do you live? Around me (VA/DC/MD) Diesel prices are consistently higher than regular gasoline, but significantly lower per gallon than premium gasoline.

[positiveions]

Wow, that thing is brutal.