Pros/Cons of Diesel cars??

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PsychoAndy

Lifer
Dec 31, 2000
10,735
0
0
Originally posted by: cavemanmoron

the only drawback is diesel fuel is a little more expensive compared to gasoline,

thats a relative term. where i live, gas is cheaper than diesel. however in larger populated areas, gas is just priced higher to meet the market price and therefore diesel is cheaper by reason of population density.
 

N8Magic

Lifer
Dec 12, 2000
11,624
1
81
hoitah

I believe this will have you stop doubting the numbers. :p

The above dyno chart is from a '01 New Beetle TDI with an Upsolute Chip, K&N drop in filter, and stock .186 injectors, .205 injectors and .216 injectors respectively.

So you were saying? :D (oh, and these numbers are wheel hp, if you want numbers closer to the ones I originally stated, add 12.8% for drivetrain loss)
 

yakko

Lifer
Apr 18, 2000
25,455
2
0
Originally posted by: N8Magic
Originally posted by: Pacfanweb
Pros of buying a diesel: Phenomenal fuel mileage, engines last forever.

Cons: Noisey, they stink, not as much power as a gas engine.

I don't find them that noisy, and diesel emissions have improved PHENOMENALLY since the introduction of the TDI engine. I never have any smoke, and it doesn't stink like a big rig.

Power? 90hp and 155lb.ft. is enough for most people. If you want to step things up, you can do the following:

- Upsolute Chip and K&N drop-in filter = $425.00 = +35hp +50lb.ft.
- .205 injectors = $600.00 installed = +30hp +55lb.ft

TOTAL -----------> $1000 in upgrades and you have a 155hp/260lb.ft tire shredding monster.

Don't forget: People buy horsepower, but they drive torque.

Nice numbers.


<----wants to steal N8Magic's VDub
 

Thegonagle

Diamond Member
Jun 8, 2000
9,773
0
71
The price of diesel fuel fluctuates more slowly than, almost independent of, gasoline. By my observation in my area, it is usually a few pennies more per gallon, but it's not significant. You'll still save money because of the excellent mileage.

The VW TDI does smell a little bit, but it's not overwhelming like older diesels. While emissions are much improved in recent times, it can't be argued that a modern gasoline engine is much cleaner at the tailpipe.
 

Nefrodite

Banned
Feb 15, 2001
7,931
0
0
polution:p they emit large particles that go deep into peoples lungs and cause resperatory problems, which is why its good we don't have a lot of diesels everywhere.


sticky fuel:p
 

compuwiz1

Admin Emeritus Elite Member
Oct 9, 1999
27,112
930
126
In some applications, they simply tow better. Case in point, is the Ford Powerstroke Diesel. If I were buying a heavy duty truck for towing, my next best option, as far as power is concerned would be the 6.8L V-10. It will not make the torque as early in the RPM range, nor will it achieve near the economy of the diesel. All things must be weighed, however. The PSD costs almost $5000 more, if you are buying a new truck, but it will also run up to 5 x the miles of a gasoline engine, if properly maintained. The immediate satisfaction is there, but the long term gains are even better.
 

Stifko

Diamond Member
Dec 8, 1999
4,799
2
81
I'd get a VW Golf TDI GL in a heartbeat if I could afford it.

NE1 notice how diesel now costs the same as reg gas? It was always much cheaper, but now in NY it is the same price.
 

geno

Lifer
Dec 26, 1999
25,074
4
0
Personally, I'm no fan of diesels in cars, I need a sportier engine ;) But, they're great on milage, and I hope the industry keeps working on refining diesel engines. I'd like to take a TDI for a spin so I can feel out the lower revs/torque curve :)

BTW: what's the redline on those things?
 

StageLeft

No Lifer
Sep 29, 2000
70,150
5
0
The new ones at least have an incredible 90 horsepower. THing is since they have so much torque the car doesn't feel like the HP is that low so in traffic you won't think you're driving with so little power...but don't plan on winning any drag races because you won't.

They're solid good cars and the engines are reliable - but of course ther eis more to a car than the engine. If gas prices are your concern it's definitely worth buying one. The new VW's have resolved many of the earlier issues with diesels like having problems starting in the cold and what not.

Plus if you don't like filling up for gas much you won't because on a tank you can go forever.
 

FeathersMcGraw

Diamond Member
Oct 17, 2001
4,041
1
0
Originally posted by: Skoorb
The new ones at least have an incredible 90 horsepower. THing is since they have so much torque the car doesn't feel like the HP is that low so in traffic you won't think you're driving with so little power...but don't plan on winning any drag races because you won't.

Okay, time to fess up: I'm car-stupid (in the exact same way my mother is computer-stupid). What's the difference between horsepower and torque? Any good car-newbie FAQ sites so I can figure out what's going on under the hood?
 

StageLeft

No Lifer
Sep 29, 2000
70,150
5
0
Originally posted by: genocide
Personally, I'm no fan of diesels in cars, I need a sportier engine ;) But, they're great on milage, and I hope the industry keeps working on refining diesel engines. I'd like to take a TDI for a spin so I can feel out the lower revs/torque curve :)

BTW: what's the redline on those things?
I believe it's about 4000 or 4500 tops...that's why you can't win any drag races with it. Although you have a lot of torque on the low end if you keep it floored you'll find you have to quickly change gears, so for regular driving it willf eel like a car with maybe 150 HP since most cars are pretty close on HP and torque...but since most cars redline at 6k+ that's why their actual performance will be better if you need to accelerate quickly.

For a person who is not interested in racing the 90 hp/155 torque seriously is very adequate. I was really impressed with the VW I diesel I drove last year constantly surprised at how much 90 HP could do on such a heavy car.

 

Murpheeee

Diamond Member
Apr 30, 2000
3,326
0
76
I have heard a rumor that there is a change in the specs on 2003 VWs.

At the moment you can get the GL, or spend an extra $1500 for the GLS (gaining power windows/mirrors, cruise etc)

Well I heard that the 2003 Jettas which have started appearing have the GLS equipment standard on the GL.
Thus saving you a bunch of cash...and making it a great deal.

If true, I would assume the '03 Golfs will be the same.
 

Haircut

Platinum Member
Apr 23, 2000
2,248
0
0
I want a BMW 330d sport.

3.0 litre inline 6, 184 hp 283 lb.ft of torque.
0-60 in 7.6 seconds and gas milage of 31 urban and 53 highway :Q
 

Triumph

Lifer
Oct 9, 1999
15,031
14
81
Originally posted by: Bluefront
Don't know much about VW diesels, but I owned a Mercedes 220 diesel for a while. And I worked on it also....had to put a set of injectors in at 38k. The previous owner had neglected regular oil changes and seized a piston at 32k. Oil changes on this car were critical....if you went past 2000 miles, it was difficult to drain.....black, thick, awful stuff came out..it would stain your hands bad. This thing had four places to drain....filter and pre-filter, pan, and cooler. I hated it.

It had glow-plugs that took almost two minutes to warm....then you could start it. Course if it was cold, say below 15f......It might not start at all, even with it's monster, expensive battery.

And it was noisy...the knocking was so bad, you thought a rod was about to go. Normal sounds from the thing.

Smelled...bad. Covered the back of the car with a sticky layer of black oil. I was constantly cleaning the thing.

Anyone saying a diesel outlasts a gas engine is crazy. It depends on how the engine is built....gas engines regularly last 300k or more. A cheap diesel engine (there have been quite a few built) won't last that long. It just depends....

I liked that Mercedes...except for the diesel engine.

First, I'm not doubting your experience with this particular diesel. But how long ago was this? The VW TDI's are LIGHT YEARS ahead of old diesel technology. Amazingly so. Also, our 1982 300D is still running strong. The body is rusting off, the seats are ripped, the dashboard is cracked, the antenna is made out of a coat hanger.... But that engine is still running as good as it did 10 years ago. Always starts in the winter, and only takes about 6 seconds before you turn it over. And this car gets NO tender loving care. None.
 

Beau

Lifer
Jun 25, 2001
17,730
0
76
www.beauscott.com
Another plus is you can run them off of vegetable oil and fryer oils :)

Linky

I have a friend who drove from Utah to Costa Rica and only bought one tank of diesel. The rest of the way, he just filled up his tank with used fryer oil from places like McDonald's.
 

incallisto

Golden Member
Apr 30, 2000
1,473
0
0
I have an 83 GMC Jimmy Sierra Classic with 983k/miles on it. I only replaced the transmission once, and everything else is original. It's 6.2litre diesel engine and averages between 22 and 24 mpg.
 

halik

Lifer
Oct 10, 2000
25,696
1
81
983k miles hahaha,
drive it a little more and then you can sell it as barely used (the tach should swirch back to 0 ) :)
 

Thegonagle

Diamond Member
Jun 8, 2000
9,773
0
71
Originally posted by: FeathersMcGraw
Originally posted by: Skoorb
The new ones at least have an incredible 90 horsepower. THing is since they have so much torque the car doesn't feel like the HP is that low so in traffic you won't think you're driving with so little power...but don't plan on winning any drag races because you won't.

Okay, time to fess up: I'm car-stupid (in the exact same way my mother is computer-stupid). What's the difference between horsepower and torque? Any good car-newbie FAQ sites so I can figure out what's going on under the hood?

(Foot-Pounds of Torque x RPM) / 5,252 = Horsepower

Recall a little bit of your basic algebra and you can see that HP is simply a culmination of torque and RPM.

Plug in a zero for either torque or RPM and solve for HP. As you can clearly see, you can?t have one without the other.

For more info from How Stuff Works:

What's with the number 5252?

What is HP and what does it mean?
 

OS

Lifer
Oct 11, 1999
15,581
1
76
Originally posted by: FeathersMcGraw
Originally posted by: Skoorb
The new ones at least have an incredible 90 horsepower. THing is since they have so much torque the car doesn't feel like the HP is that low so in traffic you won't think you're driving with so little power...but don't plan on winning any drag races because you won't.

Okay, time to fess up: I'm car-stupid (in the exact same way my mother is computer-stupid). What's the difference between horsepower and torque? Any good car-newbie FAQ sites so I can figure out what's going on under the hood?


Torque is how much twisting force the motor puts out.

HP is the power output of a motor, how much energy it can put out or how much work it can do, in a fixed amount of time.

They are different things but related.



Personally, I think it's fallacious the way torque is being sold as performance in this thread. Despite what anyone says, HP still matters and it matters a lot if you want to go fast.

A motor with a lot of torque but a low redline won't put out much power. This is because even though it turns really hard, it does so so slowly that in a given interval of time it doesn't do much work. And power is exactly how much work something can do per unit of time.

A motor with little torque, but a very fast spin, rapidly does more work in a given amount of time. Thus it has more power.



Let's take a look at a car reknown and always derided for it's lack of torque, the Integra Type-R. Relative to every other car mentioned in this thread, it's peak torque output is a piddly 130 lb-ft, half the output of the modded VW N8 mentions.

But at the same time, it has a 6.6 sec 0-60 run, which stock for stock, is faster than every diesel car mentioned in this thread. I'm almost certain that it's even faster than the modded VW. All this despite it's low torque rating.

link


Even worse, if you look at dyno graph for that TDI VW, you'll see that the torque very rapidly drops off after 2k rpms. This means the car will rapidly run out of breath as the revs increase. Gasoline engines in comparison, have torque curves that are very flat in comparison. That TDI would be great for stop and go driving, but terrible if you like to drive hard.



On a side rant, it's funny how on ATOT, people can get away with pimping crown vics as performance rides and fixing up 90 HP VWs. But when someone posts a 13 sec integra, people come out and start shouting 'ricer' and saying 13 seconds is not that fast.



 

slikmunks

Diamond Member
Apr 18, 2001
3,490
0
0
Originally posted by: OuterSquare
On a side rant, it's funny how on ATOT, people can get away with pimping crown vics as performance rides and fixing up 90 HP VWs. But when someone posts a 13 sec integra, people come out and start shouting 'ricer' and saying 13 seconds is not that fast.


hahaha, that's so true... the rice thing may be partially true at times, but it's completely worn out
 

eLiu

Diamond Member
Jun 4, 2001
6,407
1
0
I will be driving a Mercedes Benz 1985 300SD Turbodiesel. Mileage isn't as good as some of the newer diesel cars...esp the TDI equipped VWs. But 30mpg-ish (i think) is nothing to whine about =) The car is 17 years old (older than me) and running up on 200k miles. There has never been any major engine work done to it...I think the most 'extensive' job was a tune up around 100k miles. As far as power goes...acceleration from like 0-20 sucks. But after that, my diesel easily keeps pace with gas cars.

Edit:
I've been washing the car since i was like 10...(when my dad drove it) and I never noticed any really nasty grime buildup. But then again, the tailpipe is tucked under the bumper, so maybe that's why.

It's noisier than many of the newer gas cars I've ridden in, especially at idle/accelerating (when the rpms pass like 2000-2500). But the noise really isn't that bad overall; at highway speeds it's no noisier than your average gas car.