[DPetrolHead]

One of the biggest factors that come in play while choosing the car we want, especially us enthusiasts, is the heart of the car, the engine!

The Indian Car Scene now has a variety of options in terms of two types of petrol engines, the Naturally Aspirated (Non- Turbo) engine and the Turbocharged engine.



A naturally aspirated engine is an internal combustion engine in which the air intake relies solely on atmospheric pressure, which is the exact opposite of the force induction turbocharged engines use.

Even though the new trend is followed with a downsized engine with one or more turbos ( in case of sports cars and super cars) and odd number of cylinders (usually 3 such as the boosterjet engine) , I still prefer the big naturally aspirated engines and their high revving nature.


Super car manufacturers like Lamborghini and Ferrari has always preferred big V10 or V12 NA engines until now

I m not saying that turbocharged engines aren't great, I love the 1.2 TSI and 1.8 TSI motor from VW group or the 1.4L T-jet from Fiat or the newly launched 1.4 GDi in the Seltos , but the smile I get from redlining my daily Swift Dzire's 1.3NA (G-series) or the 1.5 NA of Honda City is incomparable!

The power delivery and the "pushed into the seat" feeling of turbo petrol engines can be addicting


The 1.5 NA is still among the top choices among enthusiats

So what is the take of other BHPians in this scenario? Would love to hear from all and excuse the mistakes in the post if any!

NOTE: Diesel and Supercharged Petrol engines haven't been included in this post.

Cheers!
Ankit

[sumeethaldankar]

Voted for NA. No turbo vurbo for me. Sold my Verna for one of the reasons the turbo would kick suddenly and had to keep clutching the car. Once it leapfrogged betwen a road barrier and a rick without warning leading to a scary moment probably due to the diesel torque. One more plus point of a NA engine is one does not to idle anything before switching the engine off. Also lesser moving parts means more reliability in the long run for the regular engined car.

[marutifan]

A turbocharged PFI engine would be most preferable, followed by NA PFI engine. I'll avoid GDI engines as far as possible with or without a turbocharger.

[TDCi'd]

Even though I drive a turbo diesel(I love it to bits) I still prefer NA engines for their linear acceleration. Turbo petrols that I drove(Venue and XUV300) had massive turbo lag under 2k RPM and I absolutely hated that in the stop and go traffic in my city. One of the reasons I like Ecosport diesel is the minimal turbo lag and linear acceleration (no push to the seat like 1.2 TSI or 1.2 TGDI) which actually suits my style of driving(added FE is always good!)

[tejas2323]

NA though free revving are heavy engines with less torque as compared to turbo charged engines.

This results in linear power delivery with heaviness in front of the car.

Turbo charged engines are downsized which results in weight reduction along with more torque. This feels like torquey diesel engine along with petrol smoothness so my pick would be turbo charged.

[octane_100]

A bigger free revving NA engine anyday for me. There is nothing like the linear power delivery of NA engines and also fact that they are easy on maintenance and can be thrashed makes it a natural choice for me.

[vishy76]

I would say it depends on the engine being compared. Let me quote a few examples here:

- 1.2L TSI vs 1.6 MPI from the VAG stable: This is a no brainer. If I have the moolah, I will anyday pick the 1.2 TSI over it's 1.6 NA sibling. It's a different matter altogether that the TSI is mated to an unreliable DSG, but if it were a manual, no comparison with its NA sibling at all IMHO. The 1.2 seems to be more of an exception to be honest as it has a peppy low end, something most turbo petrols struggle with. One of the many reasons why it trumps it's larger 1.6 sibling. I don't think the same will apply to the 1.0 TSI though.

- Ford's 1.5 Dragon vs 1.0 Ecoboost: i would obviously pick the dragon. Simple, the power increment offered by the Ecoboost simply isn't worth the premium you pay over the dragon and the complexity the engine itself carries.

- Kia's 1.5 NA petrol vs 1.4 turbo petrol: This example is similar to the VW case, except for the fact that the 1.4 does have a bit of turbo lag unlike the TSI which is seamless in comparison. Apart from this, the 1.4 turbo is mated to a quicker GB too as compared to the 1.5 which gets a CVT. Clearly shows who Kia is targeting here. I would pick the 1.4 for highway jaunts, though the 1.5 will more than suffice for city commutes with better low end torque.


To conclude, I would pick the NA over turbo petrols in most cases, but let me add that turbo petrols are catching up to larger NAs with better tuning (as in the case of VAG). Reliability remains a question mark for all turbo petrols due to their inherently complex nature, and another thing to note is that these are very sensitive to throttle inputs leading to variation in FE figures which many urban dwellers don't welcome. A turbo petrol might not be as efficient as an equally sized NA in city traffic though this changes on open roads where the engine sits at a constant rpm.

With downsizing and the demise of diesel engines, turbo petrols are going to be the need of the hour to be honest, atleast until electric cars gain momentum.

[SS-Traveller]

Choosing a turbocharged or naturally aspirated petrol engine is not an option for the average car buyer. Whether to install a turbocharger (or not), is a choice for the designers of the engine (and the car as a whole), based on multiple parameters:
- desired power and torque output,
- fuel economy,
- kerb weight restrictions if any,
- cost restrictions,
- use and anticipated load carrying capacity,
- anticipated fuel quality that would be used,
- emissions,
- engine bay space,
- design of the intake and exhaust (and whether turbocharger plumbing can be accommodated therein), and
- overall reliability & durability of the engine.

For a common rail diesel engine, turbocharging is almost compulsory. For fuel-injected petrol engines, it's not easy to tick a box and say, I want a turbo.

[suhaas307]

Well, I'm going to keep it quite simple.

If it's 4 cylinders or fewer: Turbocharged all the way..

However, anything more than 4 cylinders has to be naturally aspirated!

A naturally aspirated straight six or a flat six mill makes just the most sinful exhaust note, with the right modifications. And if I could ever lay my hands on naturally aspirated V8, that would hit the sweet spot.

Frankly, NA six/eight pot engines make enough / more power than you'd ever need, and will be the ideal weekend cars while you can drive a smaller capacity turbocharged car during the weekdays.

[Samba]

I admit, I was a fan of NA engines and believed in 'there is no replacement for displacement'.

But now am not much bothered whether there is a turbo or not.

Will pick a car which will respond better to my right foot.

So voted for 'others' in the poll.

For example-

Will pick a Ecosport with 1.5L Dragon over the Ecoboost, whereas for Kia Seltos, any-day my pick will be the 1.4L turbo over the 1.5L naturally aspirated engine.

I love the 1.5L i-VTEC of the City & I simultaneously love the Abarth Punto too!

[landcruiser123]

I’d say other as my answer is it depends
But I’d say N/A petrols most of the time.

Few reasons why all petrols don’t have turbos:

1. Turbos are driven by exhaust gases. Since diesels have a higher compression ratio, the exhaust gases can drive the turbine at high speeds. Petrol engines with turbos are difficult to design as the pressure generated by the exhaust gases is much lesser. Hence, the gain of using a turbo is not significant

2. Petrol engines have a tendency to knock. So port injection can’t be used and fuel has to be injected directly, requiring expensive hardware.

3. Petrol engines can naturally rev much higher due to light weight construction, hence there’s no need for turbos to produce power.

4. If petrol engines are as expensive as diesel fuel models, many people might start buying diesel powered models- especially in Europe and India.

5. IC engine is a dead technology- EVs are the future.

[GTO]

What timing! I just returned from a highway drive in a turbo-petrol (the Seltos DCT).

If the power rating is the same, give me a naturally-aspirated petrol over a turbo any which day. I am SO GLAD that the next-gen Honda City will have the sweet free-revving 1.5L, and not the 1.0L turbo seen internationally. Reasons for my preference:

- Nothing quite like a naturally-aspirated engine that revs freely to 7,000 rpm.

- No replacement for displacement .

- Simpler maintenance.

- No idling for 1 minute before & after your drive.

- Linear power delivery.

Of course, it does vary from manufacturer to manufacturer. E.g. VW, I would pick their 1.2 TSI over the boring 1.6L n/a. And turbos do have some advantages (mid-range punch, easy remaps).

[dhanushs]

To be very honest, my choice would be largely depended on the kind of engine it is.

Two things that are important to me:

- High and Free Revving nature of the engine.
- Good low-end drivability so that you are not stressed.

As long as these are met, I'm OK with Turbo or Non-Turbo. On deeper thought however, I think I'd prefer the Turbo, since I really want to fit a BOV someday on to my petrol high-revving car!

[Rajeevraj]

As few folks have already mentioned. It kind of depends. I drive the 1.2 TSI and it is perfect for my kind of driving and I love it. At the same time, I was not very happy the few drives I did in Ford's Ecoboost. The Venue was more of a neutral opinion. Same with the turbo petrol in the Nexon.

At the same time, I have enjoyed the Toyoto's 1.5L on the Etios and Honda's 1.2 in the Brio and even the 1.6L in my earlier SX4.

So in summary I guess it depends on which turbo petrol and which NA and how the manufacturer has put it together.

[vibbs]

I feel that an Apples to apples comparison is when we compare similar engines in NA and Turboed Avatar. When you downsize the engine and bolt a turbocharger to up the power and torque output you are bound to have different characteristics. Is it not?

So the poor low end is not a Turbo feature, though it is accentuated by the boost that kicks in once the turbo pools. The poor low end is because you are comparing a smaller engine (in its non turbo zone) with a larger NA engine.
So what will be answer if you consider similar displacement engines with or without turbo. Or even same engines with or without turbo?

For eg Honda's 1.5 Ivtec with and without a turbo. Or say Volkswagon 1.2 with and without turbo.

But then the answer would be too obvious is it not? Or am I missing something?