Many car enthusiasts appreciate fast acceleration in a vehicle. This in turn can lead them to wonder whether a V8 or V12 will produce greater acceleration.
V8 and V12 engines are different kinds of engines that primarily differ on the number of cylinders they have, with the V8 incorporating 8 cylinders and the V12 utilizing 12 cylinders. While in general V12 engines are more powerful than V8 engines, there are many factors affecting acceleration, and which one results in faster acceleration comes down to individual engines and vehicle specifics, rather than engine categories as a whole.
A wide variety of factors affect the acceleration of a vehicle. It’s not a simple case of saying one engine is always faster than another.
What is a V8 engine?
A V8 is an engine with a V-shaped cylinder block and eight cylinders. There are different kinds of V8 engines, such as the flatplane V8 engine and crossplane V8 engine which is the most common V8 engine in cars.
The crossplane engine has a secondary engine balance and operates more smoothly. The flatplane engine is lighter and can be revved more easily than a crossplane engine but it has a secondary engine imbalance which results in more vibration than the crossplane engine.
V8 engines are smaller than V12 engines, making them a more efficient choice when space in a vehicle is limited. V8 engines also offer better fuel economy over V12 engines as they consume less gas due to having fewer cylinders than a V12.
What is a V12 engine?
A V12 is a V-shaped engine with 12 cylinders mounted on a crankcase in two sets of six. V12 engines have a primary and secondary engine balance which does away with the need for balance shafts to reduce vibration.
In general, V12 engines are more powerful as more cylinders allow for more displacement, which in turn generates more power. An increased number of cylinders allows for the cylinders to be smaller, which increases the rev limit they can provide.
A V12 engine will tend to cost more money than a V8 as it has more components to it. It can often be heavier too (though this depends on what materials the engines are made from), so all else being equal, a V8 would offer a better power-to-weight ratio.
Other factors affecting speed
When it comes to how quickly a car can accelerate, it’s not just the type of engine that affects acceleration. Many factors affect how fast a car is, including torque, what quality of fuel it uses, the degree of traction provided by the tires, the car’s aerodynamics, and the vehicle weight.
It’s possible for V8 engines and V12 engines to produce the same amount of horsepower but also possible for either type of engine to produce more or less power than the other depending on how it’s made.
If a V8 and a V12 both produced the same amount of horsepower but the V8 weighed less and allowed for a lighter car (as the car doesn’t have to support as much engine weight), the car with the V8 would accelerate faster compared to a heavier car with a heavier V12 engine. Of course, this doesn’t take into account a variety of other factors affecting acceleration.
Torque refers to the amount of rotational force produced by an engine (and is sometimes referred to as the engine’s pulling power). Horsepower on the other hand refers to the speed at which that force is delivered.
In general, cars with greater torque are faster than cars with less torque. However, maximum torque is created across a particular rev band (the exception being electric motors). For maximum performance across the entire range of revs, the engine needs to produce maximum torque in the low rev range. Subsequently, power should take a more prominent role in higher rev ranges.
This enables the car to accelerate quickly from low to mid rev ranges, as greater torque in the lower ranges allows for faster acceleration. Electric motors enable fast acceleration because they create all of their torque at 0rpm.
Brake horsepower (bhp) is an engine’s useful available power once the amount lost to friction in mechanical parts has been accounted for. Horsepower is a measurement of an engine’s power output and in general, the more horsepower a car has, the faster it will accelerate.
Some vehicles produce high torque but low power and vice-versa. Ideally for maximum performance and quick acceleration, the vehicle should provide high power and high torque.
Additionally, engines can be turbocharged or supercharged to create more power and torque to aid in acceleration.