[Voyager-1]

We all know that the air conditioning unit draws power from the engine. For smaller capacity engines (around 1L and below), the AC can have observable impact on the car's performance. There used to be a joke that for the Maruti 800, switching off the AC would give a nitro boost to the pickup.

With the 1 liter turbo petrol engines becoming common in the market, do the reduction in engine size negatively affect the AC performance?

The 1L turbo petrol engines produce around 100-120 PS power, which is equivalent to 1.5L naturally aspirated engines. But this high power is produced only at high RPMs. Majority of the driving is spent in lower RPMs (3000-3500 and below).

So in this context, what really matters for AC performance?

[cooldude1988765]

When I test drove the Polo 1.0 didn't notice any perceivable drop in performance.


We used to own an Esteem Diesel and the running joke in our family was that we owned the only car in the world with an electronic turbo (which was the AC button)
The car made all of some 50 odd bhp and had a very very effective AC which felt like it needed around 40bhp of the engine output to function.

I really doubt any of the new age turbo engines would be having this issue.

[anb]

Originally Posted by Voyager-1

. There used to be a joke that for the Maruti 800, switching off the AC would give a nitro boost to the pickup.

With the 1 liter turbo petrol engines becoming common in the market, do the reduction in engine size negatively affect the AC performance?

The 1L turbo petrol engines produce around 100-120 PS power, which is equivalent to 1.5L naturally aspirated engines. But this high power is produced only at high RPMs. Majority of the driving is spent in lower RPMs (3000-3500 and below).

So in this context, what really matters for AC performance?

AC performance is good in 1 L engines. For petrol engines, peak power is produced at high rpm whether it’s a NA petrol or turbo petrol. Pickup is because of the torque produced by the engine. 1L produce much more torque than a 1.5L NA engine between 2000-4000 rpm. So a pickup is more for a 1L turbo engine than 1.5 L NA engine.

[goandude]

I have a 1.0 liter turbo gdi engine in my i20. AC is very effective and doesn't affect performance. It reduces fe by about 10 %.

[Voyager-1]

Originally Posted by anb

AC performance is good in 1 L engines. For petrol engines, peak power is produced at high rpm whether it’s a NA petrol or turbo petrol.

Originally Posted by goandude

I have a 1.0 liter turbo gdi engine in my i20. AC is very effective and doesn't affect performance. It reduces fe by about 10 %.

I was reading further on how much engine power the AC Compressor would consume. The estimates I saw on the internet varied anywhere from a few HPs (on a relative cool day) to even around 10 HPs (on a hot day).

So to summarize, as long as the AC Compressor gets sufficient horse power even in lower RPMs, then it will work well irrespective of the engine size or whether it is NA or turbo.

[Altocumulus]

For the 1.0 Tsi VW engines, the peak torque is from 1750 to 4000 RPM.

I hardly feel any difference with the AC on or off.

[OffRoadFun]

It's a myth petrol turbo engines generate peak RPMs torque ONLY high RPMs. The torque curve is flat for VW turbo petrol engines as early as 1700RPMs. Contrary to what is believed, a turbo charged petrol achieves peak torque earlier than a correspondending naturally aspirated engine. And hence, there is no reason to believe AC performance wil be worse in 1.0L turbo petrol, it can only be better.