bluelines:
Whoopsy:

On normal throttle applications, a NA car is more fuel efficient than a small capacity turbo car.

Small turbo cars are only efficient on test cycles. 

You got a source? Would be interesting to read.

My personal experience is the exact opposite.

 

 

Small capacity turbo cars are only fuel efficient when it is running the off boost map, like in all test cycles. During those testing cycles, I believe they specific a 0-50km time in like 10-12 seconds or something. You try doing that in real life at a traffic light, you might get shot at if you are in the USA.

Those engine replies on high boost pressure to make the power, and thus they need lower compression cylinders, which, when off boost, make them almost useless in making any power, it's perfect for test cycles, as the test do not stress engines at all. I real world driving, people have a certain acceleration target they want to hit, it may not be 0-60 in 3 seconds kind, but all will still be higher than the rate specified in testing. That also means the throttle is opened more and thus get into the boost map. 

The boost map is an especially rich mixture, the extra fuel is there to cool the cylinders. 

https://www.youtube.com/watch?v=9aO2vC_iMTI

A bigger capacity NA engine may not test well in test cycles, but in real world driving they are better as the ECU doesn't have to waste fuel to cool the cylinders, all the fuel consumed are being used for propulsion. There are no distinct on boost and off boost fuel maps for NA engines, it's basically just one map. Of course at full throttle the bigger capacity NNA engine will consume as much, if not more fuel than a small turbo engine even with the wasted fuel for cooling, but there are areas of the curve where the NA engine is more efficient, and those area mostly are during real world driving scenarios.

Here is something interesting among my cars. I have the 2.0L Turbo Golf R, ~300HP, and I also have a Honda Ridgeline, 3.5L NA V6 making ~280HP. The Ridgeline, being much heavier, still gets better mileage than the little Golf R, not much, ~1.5L/100km. I am doing ~12.4L/100km in the Honda vs 14L/100km in the Golf R. My Turbo S Exclusive is also ~14L/100km. All mostly city driving.

 

 

 


--