US Diesel's big splash introduction

[Anchorman]

Yes you need good HP but good torque (at low revs) is also important for the shove you need to get off the line.

So... good amount of HP coupled with good dollops of torque at low revs.

Problem solved

That at least considers it. Well reasoned X8

 

[Unobtanium]

Until somebody tries it there isnt much point.

Here's waiting on you, Mazda..

 

[Xeler8ing]

That at least considers it. Well reasoned X8

(thumb)

 

[Timsvt]

FWIW- https://www.greencarreports.com/new...till-mia-in-compact-crossover-utility-vehicle

 

[finch204]

Horsepower = (torque X RPM) / 5252

What that means is that torque determines a car's horsepower at a certain RPM. This means that at 2000 RPM, a diesel CX-5 which can put out 310 lb-ft of torque, is making around 118 horsepower. A petrol CX-5 makes peak torque at what, around 3200 RPM? At 3200 RPM, with 185 lb-ft of torque, a NA CX-5 is making around 112 horsepower. Even if the petrol CX-5 were making 185 lb-ft of torque at 2000 RPM, it would only be putting out 70 horsepower. This is why the diesel CX-5 will feel a lot stronger in everyday driving, because it generates more horsepower at the RPM ranges that we normally drive on.

Generally speaking, not taking into account gearing and weight, high horsepower is what makes a car fast. So a 187 horsepower CX-5, will be faster than a 175 horsepower CX-5, even if that 175 hp CX-5 makes 310 lb-ft of torque at the lower RPM range.

 

[Unobtanium]

Horsepower = (torque X RPM) / 5252

What that means is that torque determines a car's horsepower at a certain RPM. This means that at 2000 RPM, a diesel CX-5 which can put out 310 lb-ft of torque, is making around 118 horsepower. A petrol CX-5 makes peak torque at what, around 3200 RPM? At 3200 RPM, with 185 lb-ft of torque, a NA CX-5 is making around 112 horsepower. Even if the petrol CX-5 were making 185 lb-ft of torque at 2000 RPM, it would only be putting out 70 horsepower. This is why the diesel CX-5 will feel a lot stronger in everyday driving, because it generates more horsepower at the RPM ranges that we normally drive on.

Generally speaking, not taking into account gearing and weight, high horsepower is what makes a car fast. So a 187 horsepower CX-5, will be faster than a 175 horsepower CX-5, even if that 175 hp CX-5 makes 310 lb-ft of torque at the lower RPM range.

^that.

 

[shadonoz]

Torque is what is produced at the crank, it's what does the work. HP takes engine speed into account, as defined by finch's formula, and measures power. As engine speed increases, power increases until torque begins to decrease. We talk about both because torque curves are not flat [electrics not included], and the shape of the torque curve is what determines the HP curve. Knowing peak torque and HP gives us an idea of an engine's performance, but the torque curve really explains it. The HP and torque curves always intersect at 5252 rpm by definition [the formula].

We notice torque at lower engine speeds, HP at higher engine speeds. Work vs power. Working harder, making more power. The same but different.

Torque is more associated with acceleration, while HP is more associated with speed. The same but different.

Gas and diesel and electrics all have radically different torque curves, so that explains their different responses at different engine speed. Apples and oranges and kumquats.

 

[Chris_Top_Her]

Not to mention axles ratio and gearing. Not so cut n dry.

 

[Red MC]

We know maximum acceleration is achieved by selecting shift points that keep the engine RPM near peak horsepower. Here's a pretty simple explanation: Accelerating a car requires work. You increase its speed by increasing its kinetic energy. The faster you can do work = the faster you can increase kinetic energy = the faster you can acclerate. Work is power multiplied by time.

It may seem like you're wasting the diesel's generous torque output by keeping the revs well past the torque peak, and you kind of are. But when you short shift to keep the revs near the torque peak, you're wasting greater the mechanical advantage of the lower gears.

Here is something I posted earlier, a normalized acceleration vs. road speed curve for the CX-5 diesel in each of the six gears. I calculated normalized acceleration from the torque curve Mazda published in a marketing presentation along with the published ratios. Maximum acceleration comes from selecting shift points that maximize the area under the curve. I also took those shift points and overlaid them on a horsepower curve.

http://www.redmc.net/cx-5/shift_points.png
http://www.redmc.net/cx-5/horsepower_gears_6th.png

Having said all that, I don't really care about beating people in a drag race. What I like about diesels is the reserve of available torque and throttle response you have at cruising RPM.

 

[Jedi54]

2019 CX-5's getting engine upgrades
https://www.autoevolution.com/news/...-new-skyactiv-technology-in-japan-123399.html

annnnnd still no Diesel for us in the US.

 

[shadonoz]

Not to mention axles ratio and gearing. Not so cut n dry.

The relationship between HP and torque IS cut n dry... at the crank. Overall performance certainly is not.

 

[Xeler8ing]

2019 CX-5's getting engine upgrades
https://www.autoevolution.com/news/...-new-skyactiv-technology-in-japan-123399.html

Looks like we are getting this upgrade here shortly

 

[Unobtanium]

2019 CX-5's getting engine upgrades
https://www.autoevolution.com/news/...-new-skyactiv-technology-in-japan-123399.html

annnnnd still no Diesel for us in the US.

My bet is the main thing you will notice is that they re-tuned the ECU and the car isn't 0.5-0.75 seconds to 60 slower than Gen 1 anymore.

 

[myee111]

Maybe Mazda is waiting to see how much weaker Trump can make CAFE.

 

[Unobtanium]

Maybe Mazda is waiting to see how much weaker Trump can make CAFE.

Maybe Trump is waiting to see how much stronger Mazda can make Mazda.

 

[Unobtanium]

 

[Xeler8ing]

(lol2)

 

[xtrailman]

Looks like we are getting this upgrade here shortly

Do you have a date?

I would defiantly be interested in the 190ps with 450nm, really it needs that just to offset the weight the car has put on over the years, my 2013 manual was 1665kg, my 2015 1703kg (auto), and a 2017 over 1740kg, 1743kg from memory.

I would also select the all round camera if its an option.
The latter is available on a Tig now, along with a 240ps 500nm diesel option, which would be my choice, I need to target that model to get kerb weight over 1720kg for towing my 1700kg caravan.

 

[Xeler8ing]

Do you have a date?

I would defiantly be interested in the 190ps with 450nm, really it needs that just to offset the weight the car has put on over the years, my 2013 manual was 1665kg, my 2015 1703kg (auto), and a 2017 over 1740kg, 1743kg from memory.

I would also select the all round camera if its an option.
The latter is available on a Tig now, along with a 240ps 500nm diesel option, which would be my choice, I need to target that model to get kerb weight over 1720kg for towing my 1700kg caravan.

Over here, the update which includes cylinder deactivation for the 2.5L and power/torque increase for the diesel is due sometime this month or next month.

If you go by what happened with the side camera on the 2017 model, that was only made available in Japan and here in Australia.

So for 360 camera, AFAIK it's only being released here and for the top spec Akera which means again only Japan and Australia get this feature.

 

[Monterra]

Haha gotta be a little quicker next time..good one unob!!