What vehicle do you drive?

Aychamo BanBan

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Does anyone know about diesel engines?

I ask, because I just got my first diesel truck. I love it. However, when I floor it to pass other cars, it doesn't do like my old gas engines and downshift, lag, then feel the engine kick in. I just floor it and it goes, it's fast but doesn't get that acceleration feeling. Honestly this is much more refined and smooth.
 

lurkingdirk

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Does anyone know about diesel engines?

I ask, because I just got my first diesel truck. I love it. However, when I floor it to pass other cars, it doesn't do like my old gas engines and downshift, lag, then feel the engine kick in. I just floor it and it goes, it's fast but doesn't get that acceleration feeling. Honestly this is much more refined and smooth.

This depends on what diesel vehicle you have.
 

Xarpolis

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I was behind this on my way home from work the other day. Absolute beauty, with a $300k window sticker.

20201007_173535.jpg


Oh, Velocity is the local dealer that sells Ferrari, Lamborghini, Bentley, Maserati among others.
 
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Burren

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That's not built for acceleration. You could probably tow a house off its foundation if you wanted to. But don't expect to step on it and get thrown back in your seat.

That motor is a tune away from massive power gains. It's pretty easy to extract a lot of performance from big diesels. Silly, but easy.
 

Fucker

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I was behind this on my way home from work the other day. Absolute beauty, with a $300k window sticker.

View attachment 309452

Oh, Velocity is the local dealer that sells Ferrari, Lamborghini, Bentley, Maserati among others.
F8 Tributo. Foler has one on order.
 

Fucker

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That motor is a tune away from massive power gains. It's pretty easy to extract a lot of performance from big diesels. Silly, but easy.

It's also a tune away from diesel parts all over the ground. It is a Ford, after all (I have a 2018 diesel F250...bone stock). There was a guy on another forum who had his Ram Cummins tuned to the nuts and beyond. He said it would destroy his Murcielago to 100...and it did.
 

Aychamo BanBan

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That's not built for acceleration. You could probably tow a house off its foundation if you wanted to. But don't expect to step on it and get thrown back in your seat.

Well, my whole point was that I can accelerate as quick as anything else, but it just feels different. It's stll 475 hp and 1050 ftlb torque! I was just curious if diesels power curves are way diff??
 

Gamma Rays

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I used to drive my former workplace's 2WD diesel Hilux. Picking up things, deliveries etc.

It had all its power way low in the revs, 1400 - 2800, I got used to how and when to throw into the next gear. By driving that way I was able to move along quite quickly, in town that is, once you got near highway speeds, then it was a slug.
 

Fucker

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Well, my whole point was that I can accelerate as quick as anything else, but it just feels different. It's stll 475 hp and 1050 ftlb torque! I was just curious if diesels power curves are way diff??

Diesels make all of their hp at low RPM. Peak HP comes in at under 3k rpm. Peak torque comes in also at low rpm. They don't rev freely like a gas Ford or Chevrolet V8....they can't.

Beyond that, I don't know why you bought a diesel if you are wondering about how quickly it accelerates or what its main purpose is.
 

Punko

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Well, my whole point was that I can accelerate as quick as anything else, but it just feels different. It's stll 475 hp and 1050 ftlb torque! I was just curious if diesels power curves are way diff??

Diesels have their torque available during lower RPM ranges. A 2002 ferrari enzo has half torque of your car, and only gets there at 5500 rpm. This is why low powered petrol engines will stall if you try to drive off in 1st gear without giving some gas, while diesels generally won't. At low RPM the petrol engine just doesn't have the torque to move your car.

Newer petrol cars have added turbo(s) to increase torque / power at low RPM, but diesels are still ahead of them when engine size / turbo / .. are the same.

Diesels have a lower max RPM (sup Sean), which means they have to shift more often, which is a disadvantage when racing. Since diesels generally aren't oriented towards speed / sporty driving, their gears are also configured to have a wide power band, rather then a high peak performance.
 

Fucker

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Diesels have their torque available during lower RPM ranges. A 2002 ferrari enzo has half torque of your car, and only gets there at 5500 rpm. This is why low powered petrol engines will stall if you try to drive off in 1st gear without giving some gas, while diesels generally won't. At low RPM the petrol engine just doesn't have the torque to move your car.

Newer petrol cars have added turbo(s) to increase torque / power at low RPM, but diesels are still ahead of them when engine size / turbo / .. are the same.

Diesels have a lower max RPM (sup Sean), which means they have to shift more often, which is a disadvantage when racing. Since diesels generally aren't oriented towards speed / sporty driving, their gears are also configured to have a wide power band, rather then a high peak performance.

What the hell are you talking about.
 

Fucker

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Horsepower = RPM times torque divided by 5252. Pretty simple. James Watt, anyone. Further, torque is a function of cylinder size, cylinder pressure, and crankpin offset. Want more torque? Increase the cylinder size. Increase the cylinder pressure. Increase the crankpin offset. Pick any one of those for good results; pick all three for optimal results.

Diesels have lower RPM in consumer engines because you have to compress the fuck out of diesel oil to get it do anything and be efficient at it. This means heavy pistons and piston rods and cranks. This means a stout block to handle the pressure, and big everything everywhere. Big head bolts. Big mains and main bolts. Weight is the enemy of RPM, and diesels are all about weight.

A car dying in first gear has nothing to do with gas vs diesel. Mostly likely an idiot driving it. How do gears and torque multiplication, work anyone?
 

Punko

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Horsepower = RPM times torque divided by 5252. Pretty simple. James Watt, anyone. Further, torque is a function of cylinder size, cylinder pressure, and crankpin offset. Want more torque? Increase the cylinder size. Increase the cylinder pressure. Increase the crankpin offset. Pick any one of those for good results; pick all three for optimal results.

Diesels have lower RPM in consumer engines because you have to compress the fuck out of diesel oil to get it do anything and be efficient at it. This means heavy pistons and piston rods and cranks. This means a stout block to handle the pressure, and big everything everywhere. Big head bolts. Big mains and main bolts. Weight is the enemy of RPM, and diesels are all about weight.

Why can you let the clutch come up in 1st in a diesel, and will it start rolling?

As opposed to a petrol, which will shut down?

Every driving school in Belgium uses diesel engines in their manual cars. The torque available at low RPM means they are fear less likely to stall when someone doesn't apply gas while driving off, or shifts into some very low RPM range.

Never driven a manual have you?

A car dying in first gear has nothing to do with gas vs diesel.

Confirmed never driven manual.

Cars stall when the clutch is released while the car is putting out insufficient power to move itself. The engine will place power on the drivetrain, which won't move since insufficient power to get the car moving, and since the engine is putting power on something that doesn't move, it shuts down.
 
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Burren

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Why can you let the clutch come up in 1st in a diesel, and will it start rolling?

As opposed to a petrol, which will shut down?

Every driving school in Belgium uses diesel engines in their manual cars. The torque available at low RPM means they are fear less likely to stall when someone doesn't apply gas while driving off, or shifts into some very low RPM range.

Never driven a manual have you?



Confirmed never driven manual.

I've had several cars that would very happily move off the line at idle speed with zero throttle input: my Z06 and my Hellcat being the most recent. Zero to do with diesel, everything to do with torque and weight. Any car can be made that way.

Might be more common in diesel, but has nothing to do with it being exclusive to THAT engine format.

12/14 cars have been manual. All my race cars have been manual. At this time, only the wife's car is automatic.

You may like diesel and you may understand some of the mechanics of it and some of the advantages, but don't make sweeping general statements that aren't true. You'll get caught out.

Anyway, this isn't a thread for tearing people down. Leave that to the politics section.
 
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Punko

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I've had several cars that would very happily move off the line at idle speed with zero throttle input: my Z06 and my Hellcat being the most recent. Zero to do with diesel, everything to do with torque and weight. Any car can be made that way.

Might be more common in diesel, but has nothing to do with it being exclusive to THAT engine format.

12/14 cars have been manual. All my race cars have been manual. At this time, only the wife's car is automatic.

You may like diesel and you may understand some of the mechanics of it and some of the advantages, but don't make sweeping general statements that aren't true. You'll get caught out.

Anyway, this isn't a thread for tearing people down. Leave that to the politics section.

Those are not "average" petrol cars but you know that of course.

From wiki:

The power band of an internal combustion engine or electric motor is the range of operating speeds under which the engine or motor is able to operate most efficiently. While engines and motors have a large range of operating speeds, the power band is usually a much smaller range of engine speed, only half or less of the total engine speed range (electric motors are an exception—see the section on electric motors below).

Specifically, power band is the range of RPM around peak power output. The power band of an internal combustion gasoline automobile engine typically starts at midrange engine speeds (around 4,000 RPM) where maximum torque is produced, and ends close to the redline after reaching maximum power between 5,000 and 6,500 RPM. Diesel engines in cars and small trucks may develop maximum torque below 2,000 RPM with the power peak below 5,000 RPM.
 
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lurkingdirk

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I have a Hyundai Sonata, and if I work it just right, I can get it going without any gas. But it's tricky, slow clutch work. It's not diesel.
 
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Gamma Rays

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With most modern cars, you can move it around at low speeds ( crawl ) without needing to give it any gas.

It's the car ECU doing it's own thing to maintain a set idle speed, AFAIK.

A sudden lift of the clutch will be too much for it and you'll stall.

I do it mostly when pulling out of my carport, I'm only going to move a short distance before stopping and getting out to close/lock the door. Second nature to me now as I'm someone who leaves for work at 5:15 am so I am being polite, most other people are still sleeping.