I know in the last 30 years turbos and superchargers have made it easier to make power, but I always hear about huge 7 or 8 liter engines made in the 70s or earlier, that will make like 200 hp at best. How is it possible to get so little out of so much displacement?
In: 37
Short answer: Better combustion efficiency, airflow, fuel control and lots more RPM.
HP = (Torque(lb/ft) * RPM)/5280
The original horse power was one horse lifting 1 pound 1 mile (5280 feet) in one minute
So a motorcycle example, BMW R1000rr ~1 liter displacement 205hp @ 13,000 rpm is over 200hp / liter naturally aspirated. The bike still makes ~83 lb/ft of torque at 13,000 rpm. Enough fuel and air into the engine though the injectors. Then the correct compression, ignition and power stroke. Then the whole motor is designed to be optimal for this power.
Nothing off of a race track was spinning 13,000 RPM in the 1970’s..
Latest Answers