Turbo engines are taking over

pinball wizard said:
Like a polo gti, or something like that?
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Not quite as that was a Supercharger + Turbo on the 1.4. But the supercharger was probably there to compensate for it somewhat yes.

New one is a 1.8T which is what I consider a reasonable size.

But think more along the lines of say the Mitsubishi Lancer Evo FQ series with 2.0 litre motors but monstrous turbos to put it in supercar territory.

For your normal daily drivers it's a non-issue really.
 
Bakkies with turbocharged diesel engines have been around for many years. They have reliably chalked up many hundreds of thousands of kilometres without engine failure. The qualifying aspect is that this has been achieved at relatively low rpm compared to a petrol motor.

Many years ago BMWs with turbo diesel motors were failing at an alarming rate. Some blamed rpm while others pointed fingers at the quality of diesel.

I've often heard that our fuel is not nearly up to the standard of other countries where turbo engines are in the mode and that some OEMs are just a little bit wary of the reliability of petrol engined turbo motors.

While turbo motors have very good torque at low rpm it does disappear alarmingly when the revs get close to the red line and this is where it matters to me. When I'm running at say, 4500rpm and need to call on power, I drop down into 5th and floor it. I can overtake a lot more quickly than the guy in a turbo. I'm at the coast so altitude does not feature.

So for now, I'll stick to my tjorrie on the rocks without any mixer.
 
Its going to be interesting to see what happens when the "Free Valve" type technology becomes integrated with turbocharging these small displacement motors.
[video=youtube;f4p-55a3WV8]https://www.youtube.com/watch?v=f4p-55a3WV8[/video]
 
stroller said:
While turbo motors have very good torque at low rpm it does disappear alarmingly when the revs get close to the red line and this is where it matters to me. When I'm running at say, 4500rpm and need to call on power, I drop down into 5th and floor it. I can overtake a lot more quickly than the guy in a turbo. I'm at the coast so altitude does not feature.
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That's a very generic and blanketed statement to make.

The torque delivery of the car is based on how it was designed to deliver torque not so much just because it's got a turbo.

Usually on smaller engines with small turbos it would be purposely specced like this to increase your every day low end torque.

On larger engines with larger turbos it can again be tuned to deliver higher end torque because the larger engine alone is enough to deliver the bottom end torque.

I could argue that because I have a turbo car I don't need to gear down and floor it at all, because the torque is right there in the middle.

I certainly don't feel any drop off in torque as I climb up the revs in my car, if anything I would say the car has another 2000rpm left the way it pulls at the top end and I expect it to peak and dip compared to other cars.

Look at a 2.0 N/A Golf it puts out 200Nm at 3250-4250.

The 2.0T variant outputs 280Nm at 1800-5000 almost a 1/3rd more for a much larger rev range.

It's infinitely more torque friendly than it's turboless variant of the same capacity.

****

I don't know what car you are driving, but I'm willing to bet it won't overtake anything faster than a similar turbo car, and probably a whole lot slower.

It's simply a perception of the power delivery that you have.
 
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Beachless said:
Wow interesting, thanks for posting.
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Here's the original video. Better quality.

[video=youtube_share;Bch5B23_pu0]https://youtu.be/Bch5B23_pu0?list=PLHa6PXrV-yIgnXSYFT07BouKhEhyFuWnf[/video]
 
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I would say that is a very narrow way of looking at things, stating that a turbocharger alone can boost efficiency is a little narrow.

An internal combustion engine is a woefully inefficient object, by design.
It produces heat as well as noise, it also suffers great mechanical losses before the power even hits the gearbox, where it is subject to more losses.

Though "more efficient" N/A engines have been made, it takes a bucket load of careful consideration. For example. Combustion chamber, shape and size. Smaller combustion chambers require less fuel and can handle more dynamic compression(story for another thread) than a bigger one, another cool characteristic is that you can run a lower octane fuel at a higher compression ratio - the higher the better in terms of N/A efficiency.

Another thing to note in determining the efficiency of an engine in general is valve angle, wider valve angles make the chamber a lot bigger, which needs more fuel to get an equivalent burn as compared to a smaller chamber. Now a great example of this is Honda's K20 - it has a tight, I think it's a 21 degree valve angle and 23cc combustion chamber...it is a very efficient engine, but it has no bottom end torque, at all. It also causes a packaging issue as the motor is very tall. The reason for that is the valve angle, which causes the inlet and exhaust ports to be quite shirt, but very steep, which makes the cylinder taller to accommodate them.

If you look at the BDA or C20XE(Opel Superboss engine, very similar to the BDA) it has a 51 degree valve angle and a long, curved ports. Great for packing, produces better low end torque, but the chambers are a little bigger and these motors are highly susceptible it pinking(pre-ignition)


Superbike engines for example are supposed to be highly efficient...but because they spend a lot of time laboring through traffic, they are not. Where as someone with a Comparable CC 2 cylinder double thumper gets great mileage due to the fact that it has low down torque.

Which leads into the next point....crank and cylinder configuration....Bore to stroke ratios. If a motor, has a "Square" bore x stroke" it will offer good low down torque and the ability to rev higher than undersqaure engines. Undersquare engines will give you a heaps of torque and then another heap for good measure, but they refuse, under all circumstances to rev. As compared to oversquare engines, which want to be strung out...constantly.

Then comes the nitty gritty things, like sparkplug placement, valve splay, valve size, piston shape, piston skirt size, piston ring material, bearing size and material and type, rod to stroke ratio(quite important).....blah, blah, humbug.
 
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I find that despite claims, fuel consumption on petrol turbos is always higher for me than on a N/A engines of equivalent size. This is because it is so tempting to use the full power of the engine at every opportunity to "get ahead" of traffic and enjoy the car.

A N/A car feels pap, so you tend to just chill and let the faster cars overtake you. It is too much effort to rev the engine to death to speed up.
 
Gaz{M} said:
I find that despite claims, fuel consumption on petrol turbos is always higher for me than on a N/A engines of equivalent size. This is because it is so tempting to use the full power of the engine at every opportunity to "get ahead" of traffic and enjoy the car.

A N/A car feels pap, so you tend to just chill and let the faster cars overtake you. It is too much effort to rev the engine to death to speed up.
Click to expand...

That's not a fair comparison as most turbo engines produce more power than an NA engine of the same size. The idea is to get a turbo engine with less displacement and the same/more power than a bigger NA engine. These smaller turbo cars can have better fuel economy without a loss in kw.

For example: a 92kw 1 litre Ford ecoboost Fiesta is equivalent to the 1.6 litre in power(88kw), but is more economical.

http://www.cars.co.za/newcars/Ford/Fiesta/3-door-1.6-Titanium/#.V_9Ls_B96Uk

http://www.cars.co.za/newcars/Ford/Fiesta/5-door-1.0T-Titanium/#.V_9MjPB96Uk
 
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Gaz{M} said:
I find that despite claims, fuel consumption on petrol turbos is always higher for me than on a N/A engines of equivalent size. This is because it is so tempting to use the full power of the engine at every opportunity to "get ahead" of traffic and enjoy the car.

A N/A car feels pap, so you tend to just chill and let the faster cars overtake you. It is too much effort to rev the engine to death to speed up.
Click to expand...

You need to compare actual power output...not size.

Of course it will be using more fuel if it's pushing more power.

Where the efficiency concept comes from is getting more from less by use of a turbo setup.

****

I see phoenix99 got there first.
 
SauRoNZA said:
You need to compare actual power output...not size.

Of course it will be using more fuel if it's pushing more power.

Where the efficiency concept comes from is getting more from less by use of a turbo setup.

****

I see phoenix99 got there first.
Click to expand...

Yup
Smaller displacement = lighter, therefore less energy wasted on moving components around.
 
I'm quite happy with the 15.2 km/l (mixed cycle) I get from my 1.6 Turbo. Personally, will never by a NA car again.
 
Drifter said:
I'm quite happy with the 15.2 km/l (mixed cycle) I get from my 1.6 Turbo. Personally, will never by a NA car again.
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Yoh that's pretty damn decent.

Is that even when you spank it? Or just regular day to day.

I mean my bike only get 18-19 km/l.
 
That's regular day to day, with a bit of spanking in between. If I take to the track, it drinks quite a bit more.
 
Dr.G said:
Its going to be interesting to see what happens when the "Free Valve" type technology becomes integrated with turbocharging these small displacement motors.
Snip
Click to expand...

Very interesting thanks .
 
SauRoNZA said:
That's a very generic and blanketed statement to make.

The torque delivery of the car is based on how it was designed to deliver torque not so much just because it's got a turbo.

Usually on smaller engines with small turbos it would be purposely specced like this to increase your every day low end torque.

On larger engines with larger turbos it can again be tuned to deliver higher end torque because the larger engine alone is enough to deliver the bottom end torque.

I could argue that because I have a turbo car I don't need to gear down and floor it at all, because the torque is right there in the middle.

I certainly don't feel any drop off in torque as I climb up the revs in my car, if anything I would say the car has another 2000rpm left the way it pulls at the top end and I expect it to peak and dip compared to other cars.

Look at a 2.0 N/A Golf it puts out 200Nm at 3250-4250.

The 2.0T variant outputs 280Nm at 1800-5000 almost a 1/3rd more for a much larger rev range.

It's infinitely more torque friendly than it's turboless variant of the same capacity.

****

I don't know what car you are driving, but I'm willing to bet it won't overtake anything faster than a similar turbo car, and probably a whole lot slower.

It's simply a perception of the power delivery that you have.
Click to expand...

Come with me.
You are in my friend's 2013 Kuga 1.6 Eco boost and I'm in my 2013 Honda CR_V 2l and we drive from Botrivier to Riviersonderend on the N2.
There are quite a few long climbs.
You won't see my rear number plate, not because you are in front of me, it'll be because you are so far behind!
 
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