Puma Axed except for EV

[Crazy Dazz]

I've never quite understood why the minimum size for a modern 4 cylinder, seems to be around 1.2L?

With the latest tread towards smaller engines with turbos, there's a lot of manufacturers coming out with 3-cylinder jobbies.
It seems to me that's a big sacrifice, considering the loss of balance.

Don't get me wrong, most of them are doing a great job to overcome the inherent problems. I'm just not sure I understand the need?

In something like a Puma, it's not a question of space. And I'm not sure the cost savings would be worth it.
It would be lighter, but it seems like there's a technological resistance. Perhaps beyond a certain point, making a 4-cyliner smaller just doesn't deliver the fuel savings??

[DFB FGXR6]

Originally Posted by Crazy Dazz

I've never quite understood why the minimum size for a modern 4 cylinder, seems to be around 1.2L?

With the latest tread towards smaller engines with turbos, there's a lot of manufacturers coming out with 3-cylinder jobbies.
It seems to me that's a big sacrifice, considering the loss of balance.

Don't get me wrong, most of them are doing a great job to overcome the inherent problems. I'm just not sure I understand the need?

In something like a Puma, it's not a question of space. And I'm not sure the cost savings would be worth it.
It would be lighter, but it seems like there's a technological resistance. Perhaps beyond a certain point, making a 4-cyliner smaller just doesn't deliver the fuel savings??

Cost per unit is what makes the 3-cylinder an attractive proposition to a car maker. As you say, we are now at the point where dropping a cylinder doesn't mean dropping performance. So, why have that extra cylinder when they can chop cost out of the equation.

Think of it like this -

- Smaller block, less material
- Smaller head, less material
- Smaller crank, less material
- Smaller oil pan, less material
- Smaller valve cover, less material
- Smaller intake and exhaust manifolds, less material
- One less piston, rod and associated hardware
- Four less valves, valve springs, followers.
- Smaller gaskets, seals ect.

Then, assembling all of that is quicker on the line. Overall, the cost per engine is lower, which adds up over the course of the engine's lifespan. We are talking hundreds of millions of dollars in savings here. In theory, servicing costs will be lower for the customer as well.

So, I guess the question becomes, why carry around that extra cylinder when its absence for the most part wont be noticed by the customer.

For the record, I don't want to own a 3-cylinder vehicle, but I don't hate the format either because the Ford versions are really nice to drive and sound good too.

[Franco Cozzo]

I got no problem with the three cylinder turbo job, would rather see naturally aspirated 4 cylinder engines discontinued and replaced with turbo 3 cylinder engines.

You can make the same amount of torque but bring it in from 1500-2000 RPM on the turbo 3, instead of at 4000 RPM on a naturally aspirated 4 cylinder engine.

Makes for a way nicer car to live with on a daily basis with the turbo 3.

With what the Fiesta ST is like to drive with its peak torque coming in from 1500 RPM and maintaining it all the way out to 5000 RPM, makes for a very nice manual car to drive.

[DFB FGXR6]

Originally Posted by Franco Cozzo

I got no problem with the three cylinder turbo job, would rather see naturally aspirated 4 cylinder engines discontinued and replaced with turbo 3 cylinder engines.

You can make the same amount of torque but bring it in from 1500-2000 RPM on the turbo 3, instead of at 4000 RPM on a naturally aspirated 4 cylinder engine.

Makes for a way nicer car to live with on a daily basis with the turbo 3.

With what the Fiesta ST is like to drive with its peak torque coming in from 1500 RPM and maintaining it all the way out to 5000 RPM, makes for a very nice manual car to drive.

The interesting thing I noticed was how quiet the 3-cylinder EcoBoost is compared to a typical naturally aspirated 4-cylinder, even at the top end. Less moving parts, less noise. The turbo would naturally muffle the noise as well.

[kevino]

I have had two different Vw service guys tell me that the Vw 1 litre three cyl petrol ( which comes in at least three times of ke/torque) is the best motor Vw make.
The top tune is 85 kw and 200 nm torque at 2000 rpm
Whereas in my Puma
The Ford three cyl is 92 kw and 170 nm torque at 1400 or 1500 rpm
I haven’t driven the 85 kw tune
But my wife’s Polo is 70 kw and 175nm and is really laggy from take off while the Puma leaps out of the blocks
Maybe auto gearbox issues

[kevino]

Three tunes of kw/torque

[Franco Cozzo]

Originally Posted by kevino

The Ford three cyl is 92 kw and 170 nm torque at 1400 or 1500 rpm
I haven’t driven the 85 kw tune
But my wife’s Polo is 70 kw and 175nm and is really laggy from take off while the Puma leaps out of the blocks
Maybe auto gearbox issues

Thats the beauty of the Ecoboost engines, diesel like torque down low but power up top and unleaded servicing and running costs, they have a super wide torque band which just makes for beautiful cars to drive.


That 92KW/170NM is the same figures as the WZ Fiesta Sport, same engine I guess

[kevino]

Yeah they are nice
Although hills dull the Puma the extra suv pork ( body weight) slows it up

[Franco Cozzo]

Originally Posted by kevino

Yeah they are nice
Although hills dull the Puma the extra suv pork ( body weight) slows it up

1106kg for the WZ Fiesta Sport with the same engine
1291kg for the Puma

Thats not as bad as I thought it was, but its still a good ~280kg or there abouts.

[Crazy Dazz]

Originally Posted by DFB FGXR6

Cost per unit is what makes the 3-cylinder an attractive proposition to a car maker.

I get that it's cheaper, but is that always a good thing?

That said, I wonder if part of the cost saving is utilising existing head designs and technology, rather than designing an entirely new engine of that size.

Originally Posted by Franco Cozzo

I got no problem with the three cylinder turbo job, would rather see naturally aspirated 4 cylinder engines discontinued and replaced with turbo 3 cylinder engines.

But that's not really my question.
If you want to turbo-charge a 1.0L engine, why not do it to a 1.0L 4-cylinder.

[asagaai]

Originally Posted by DFB FGXR6

The interesting thing I noticed was how quiet the 3-cylinder EcoBoost is compared to a typical naturally aspirated 4-cylinder, even at the top end. Less moving parts, less noise. The turbo would naturally muffle the noise as well.

I used to have a Honda euro 2.4 vtec manual, and when revved above 7,000 rpm there was this nice mechanical hard edged rattle that sounded f**ing great.

My Fiesta St standard had a throbby deep lower bass sound, but revving it was blah- there was no hard brassy edge or mechanical rasp and rattle of the good type like a good sporty vtec wrung out.

I then put on an alloy Mountune intake induction elbow to replace the plastic OEM intake elbow that had a restriction. What I immediately noticed was the engine sounds a bit more brassy edged even driven normally, has lost some of the standard engine muddy low sound, and when I rev it out it gets that mechanical rasping rattle edge sound that is great.

With a Dreamscience stage 1 99+ tune with a mix of e85 running at some 240 odd hp with 385 nm, the engine is a lot more brassy mechanical rasping edged which sounds great revved, which I just love. It certainly now is not a quiet engine, and I am talking induction sound only when revved.

I think plastic is a great sound deadener on critical "trumpet " sound elements on an engine, but alloy metals on these "trumpet" sound components transmits the higher brassy edge of sound so much better.

[asagaai]

Originally Posted by Crazy Dazz

But that's not really my question.
If you want to turbo-charge a 1.0L engine, why not do it to a 1.0L 4-cylinder.

A couple of things, a 3 cylinder has more character than a 4 cylinder.

Also, a 3 cylinder often is designed with stroke etc and tuned to produce more torque but less power than a similar sized 4 cylinder engine. So it feels like a big lazy engine because of that characteristic.