Eli5: 2 cars have the same Horsepower but different engine in terms of displacement (2.0L TDI vs 3.0L TDI) but what difference does it make and which one is better?

Question

Eli5: 2 cars have the same Horsepower but different engine in terms of displacement (2.0L TDI vs 3.0L TDI) but what difference does it make and which one is better?

In: 87

Answer 1

Grandpa always said no replacement for displacement.

The 3.0L has more overall potential than the 2.0L, even if they were stock the same horsepower the overall engine likely has more room for modifications to further improve performance.

For instance both of the above motors are turbo diesels, the 3.0L can hold more overall air and hence theoretically can hold more charged air.

A 1 PSI improvement to either motor will mean the 3.0L will have more overall power as a result.

That said, for every 10lbs of weight lost you effectively gain 1 HP (in terms of performance).

Generally speaking the smaller motors also have higher redlines than larger motors too, higher RPM = higher average power.

HP figures on motors are peak power, that value doesn’t mean much… average power does and even moreso average wheel horsepower.

If an NA motor reaches 400HP at 7200 RPM and the turbocharged vehicle reaches 400HP at 2800 RPM, the turbocharged vehicle is going to be considerably quicker because it has higher average power.