Originally Posted by Devil Dog
There's no replacement for displacement...
Originally Posted by rbryan4
Sometimes there is. The 5.3L Chevy V8 has 355hp and 383lb-ft of torque, and the 2.7L Ford Ecoboost V6 has 325 hp and 375lb-ft of torque. Only slightly less torque and 30 less HP. For an engine with "displacement" less than half of the V8, not bad. The 3.5L Ecoboost has 365 hp and 400lb-ft of torque. More than the Chevy V8 with 33% LESS displacement.
Yes, supercharging (turbocharging in this case) is the most straightforward replacement for displacement.
Ford's online specs for the F-150
are almost the same, and here they are with the speeds as well:
2.7L EcoBoostŪ V6: 325 hp @ 5750 rpm, 375 lb-ft @ 3000 rpm
3.5L EcoBoostŪ V6: 365 hp @ 5000 rpm, 420 lb-ft @ 2500 rpm
5.3L Chevy V8: 67 hp/L, 72 lb-ft/L
2.7L Ford EcoBoost: 120hp/L, 139 lb-ft/L
3.5L Ford EcoBoost: 104hp/L, 120 lb-ft/L
Torque is the product of displacement, multiplied by the degree to which air is packed in by supercharging. Power is torque multiplied by speed. It's fundamentally a matter of getting air through the engine and burning fuel with all of it, although of course the details are not so simple!
The 3.5L EcoBoost produces less torque for each unit of displacement than the 2.7L, suggesting that it runs less peak boost (perhaps limited by induction, exhaust, or flow through the head). The 3.5L also produces less power per litre, simply because it produces its peak power at a lower speed.
By coincidence, the EcoBoost 3.5L has the same peak power output as my motorhome's Ford 6.8L V10... which is not turbocharged.
All modern diesel engines (other than the most basic small engines not used in vehicles) are turbocharged. Although commercial truck and equipment engines are large - displacement is important - turbocharging is to some extent certainly a replacement for displacement.