Turbo vs NA

Not really as the engine has to be tailored for forced induction.

I wasn't talking about supercharges at all as these use energy due to being belt driven.

There are no instances of petrol engines i know of were a turbo has been used to increase efficiency. If you know of one please tell me.

Turbos are used to increase power. An engine built for forced induction could not cope without the turbo/supercharger. An N/A engine is again not usually built for boost. High compression ratio means very limited boost and cast pistons/con rods mean they cannot really take it either.

For arguments sake if you were to strap a turbo to an N/A engine with a moderate level of boost and fueling to match the efficiency of said engine would increase.

I think not.
 
CraigN said:
For arguments sake if you were to strap a turbo to an N/A engine with a moderate level of boost and fueling to match the efficiency of said engine would increase.
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I take it you mean fuel efficiency? As in your example volumetric efficiency may increase, possibly other measures of efficiency too.
 
CraigN said:
Not really as the engine has to be tailored for forced induction.
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I am not gonna quote the rest of the bilge you posted, suffice as to say you are confusing economy with efficiency.

As burns states, you really need to be a bit more clear in what you say.

It doesn't even work with economy either, as a 200 bhp turbo engine vs a 200 bhp N/A engine can both be equally economical in a given situation, at max power, the improve volumetric and thermodynamic efficiency of the turbo engine may actually mean it is more economical, take a look at the figures for a 1.4tfsi Golf vs an equivalent performing naturally aspirated car. http://autospeed.com/cms/A_109931/article.html go read and learn.

Nobody has said just slap a turbo on a N/A engine, only you have used that to try an explain away your inaccurate post.

Popular Mechanics said:
The Bottom Line
So just how much fuel can a turbocharged gas engine save? Well, that depends, of course, on what you're comparing it to and whom you ask. It's safe to say, however, that a small, modern, gasoline-turbo engine will save about 8 to 10 percent over a larger engine that makes similar power and torque. There are side benefits to turbocharging small engines too--such as reduced weight. Ford's Brett Hinds says that the upcoming EcoBoost V6 is 30 pounds lighter than a V8. That may not sound like much, but every bit counts. And that's especially true, as automakers will continue to hunt for even more fuel efficiency in the coming years.
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http://www.popularmechanics.com/cars/how-to/4306310?page=1

http://en.wikipedia.org/wiki/Volumetric_efficiency
 
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I have owned both an 03 Impreza which was remapped and a 04 Monaro ... I prefer the Impreza for country roads and the Monaro for motorways & long journeys. Both sounded great but I preferred the Impreza's sound tbh but then again the Monaro with a wortec exhaust sounds amazing (this was expensive tho). I sold the monaro and have recently returned to a turbo ... an MR2 which tbh is ******* awesome, purchased in the spare of the moment off ebay for £881 :eek::cool: great sound driving position, handling, power ... should have brought one of these ages ago!

So my answer is Turbo :D
 
PMKeates said:
VTEC has become synonymous with higher-power small-displacement engines. Take the Civic Type-R EK9; introduced in 1998, it featured 185 HP from a 1.6L, giving it 116 HP/litre. It had a very distinctive driving style and nobody else was coming close at the time. The EP3 successor, introduced in 2001, made 200 HP from a 2.0L. The car retailed at £20,000. Toyota had something similar in the VVTL-i Celica, but that was about it. VANOS, Twin Spark and all the other technologies were never packaged and offered in such applications.

VTEC is by far the most prolific and well-known of the technologies used to enhance small-capacity engine performance in everyday cars. Combine that with virtually no competition in this market, I think it's very fare for people to imagine VTEC as an entire performance delivery style unto itself; it basically is!
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Not particulary, VTEC is just Hondas version and was more well known due to its marketing, Nissan VVL, Mitsubishi MIVEC and as you mentioned Toyota VVTL-I were all alternatives although the VVTL-I wasnt just found in the Celica. I think its the Nissan version that holds the highest power output for displacement

The interesting thing is that most manufactures binned off their versions years ago where as Honda has carried on the VTEC brand
 
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Matt82 said:
better than an NA, because
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Actually, you can say similar about most car equivalents...

Subaru Impreza 2000 Turbo AWD vs Subaru Impreza 2000 Sport AWD
Golf 2.0 fsi vs Golf 2.0 tfsi

I think the only way to compare fairly is to compare them when they have similar power outputs though, for example, a 2.0 turbo vs a 3.5v8 say.

Generally the v8 would have better response but the turbo would be lighter so you get different characteristics.

The Monaro vs Subaru Sti above said it all about how the 2 shine when looking at similar outputs.
 
nucastle said:
What's all this talk of VTEC like it's some kind of unique technology.

Variable valve timing is used by loads of manufacturers these days, as are engines with cam phasing.
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Even my boring Ford Focus does it. Admittedly it doesn't kick in until about 3.5k-4k revs, and by then you're usually at the speed you want to get to, but it can still be fun to gun it in 2nd and feel the little jump in power.
 
With powerful cars I've not really noticed much difference. I had a 400hp R34 RB25 (single Turbo), swapped the engine to 500hp RB26 (twin Turbo) and I've now got a 4L V8 BMW and the response feels similar in all of them, you plant your foot and away you go with only a split second delay!
 
ianh said:
With powerful cars I've not really noticed much difference. I had a 400hp R34 RB25 (single Turbo), swapped the engine to 500hp RB26 (twin Turbo) and I've now got a 4L V8 BMW and the response feels similar in all of them, you plant your foot and away you go with only a split second delay!
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Not driven either of the above cars but on the cars i owned there was a definite difference ... one was a big kick the other was smooth!
 
Dr Who said:
I am not gonna quote the rest of the bilge you posted, suffice as to say you are confusing economy with efficiency.

As burns states, you really need to be a bit more clear in what you say.

It doesn't even work with economy either, as a 200 bhp turbo engine vs a 200 bhp N/A engine can both be equally economical in a given situation, at max power, the improve volumetric and thermodynamic efficiency of the turbo engine may actually mean it is more economical, take a look at the figures for a 1.4tfsi Golf vs an equivalent performing naturally aspirated car. http://autospeed.com/cms/A_109931/article.html go read and learn.
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That article has a fair bit of crap in it. It says that a turbo must increase thermal efficiency simply because it uses energy which is normally wasted; if it converted this energy directly to useful output that would indeed be the case, but it simply doesn't. Some of the energy lost by pumping losses on the exhaust stroke will be recovered on the intake stroke, but not all. A turbo effectively uses that waste exhaust energy to allow you to burn more fuel.

Turbochargers are basically only useful for economy purposes when combined with downsized engines, and then only if you are running off boost or at low boost for most of the time.
 
whenever someone mentions this subject a certain Ford 3V Modular 4.6L V8 engine with Saleen 2.3L Twin-Screw Supercharger springs to mind for me.
 
The only turbo I've driven was a Focus ST and I enjoyed that. The Clio is N/A and sort of feels like it has a turbo kick in at 5k, probably just map though. My next car will hopefully have a turbo on it :)
 
Vonhelmet said:
Even my boring Ford Focus does it. Admittedly it doesn't kick in until about 3.5k-4k revs, and by then you're usually at the speed you want to get to, but it can still be fun to gun it in 2nd and feel the little jump in power.
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Its not the timing thats the real attribute, its shifting a valve lift valve from 6.5 mm to 10.8 in a fraction of second with the associated change in engine output and induction sound.
 
PMKeates said:
VTEC has become synonymous with higher-power small-displacement engines. Take the Civic Type-R EK9; introduced in 1998, it featured 185 HP from a 1.6L, giving it 116 HP/litre. It had a very distinctive driving style and nobody else was coming close at the time.
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I think not. Do a google search for the Nissan Pulsar VZR N1. 1998 123bhp/litre. I have a hybrid in my primera. It's a Sr20Ve with Sr16Ve cams and a few other goodies and I can tell you unlike the VTEC these engines have better torque. I still can not understand why Nissan didn't use the engine more because it was and still is a fantastic engine.

I only have 200+ BHP but there is nothing like the sound of a screaming engine shifting at 8k :D. My other car a remapped 2.2 turbo diesel Almera Tino is running 160bhp but just doesn't feel the same.
 
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