Engine development for cars so far has taken high technique in designing, powering, and mode efficiency. This is in regards to a V-style layout or structure engine for most modern vehicles. One of the most V-style engine layouts featuring high-quality today is a v8 engine. Particularly, V8 engines compacted the large sizes of old engines that were used to power heavy vehicles.
Considering the sizes of old versions of engines used in the early days, V8 engines today are among the most convenient engines that provide sufficient speed even for heavy vehicles. You may wonder why these V layout engines are called v8.
These engines contain eight cylinders that are mounted on the crankshaft case. The mounting of eight cylinders is in 2-banks each bank with four cylinders. Alongside that, there are eight pistons connected under one crankshaft. The “8” in v8 represents firing times the pistons will fire the engine.
With the many cylinders in the v8 engine and pistons, you may be wondering how many crankshafts are in the v8 engine. The truth is many, or the most common v8 engines have only a crankshaft.
Why does a v8 have one or more crankshafts?
Internal combustion uses only one crankshaft and doesn’t depend on the number of cylinders. There can be more than one camshaft from a V engine to another, depending on the engine geometry. The purpose of the crankshaft in a V8 engine is to help conversion of linear motion to a rotating motion; therefore, no need to have multiple crankshafts serving the same motion.
Again, the V8 engine has eight cylinders connected to one crankshaft, and this does not give room for more crankshafts due to limited space. This defines why most v8 have one crankshaft.
Types of v8 engine crankshaft
A V8 engine is featured to use either one of the two crankshafts. There are types of crankshafts, cross-plane crank, and flat-plane crank.
1. Flat-plane cranks
These cranks are primarily used in designing hypercars and uber-expensive supercars. They are featured with single crankpins or on a spaced four-cylinder inline cranking to enhance several rods. On how they operate, they always alternate from bank to bank no matter their firing order.
The benefit of this alternation helps to reduce header complexes crossing from bank to bank, therefore obtaining optimum scavenge exhaustion.
Flat-plane cranks rep up quickly as they don’t require heavy counterweights, although this makes them be affected by secondary vibrations.
Advantages of the flat-plane crank
- They produce good balance due to their lightweight (creation less inertia)
- Tuning for maximum performance with headers is easy.
Examples of Cars that use Flat-Plane Cranks
- Ferrari F430
- Lotus Esprit
- Porsche 918
- McLaren P1
2. Cross plane crank
This is the most common crankshaft that is primarily seen in hot rod engine models. The crank got its name from the four crankpins placed in the two levels balanced by ninety degrees. Generally, the two exterior pins are positioned in a hundred and eighty degrees plans. It makes a (+) shape when examined from the end of the four points, arranged in ninety-degree intervals.
One typical firing sequence is 1-8-4-3-6-5-7-2, with automobiles numbered in even numbers on the traveler’s side while the odd-numbered barrels are on the opposite side. These cranks have two following exhausts hurling on one of the banks, granting them the muscle vehicle noise that most people like.
While its exhaust fumes scavenging is not as effective as the flat plane, its rumble sound is worth it. Its design compels a vaster counterforce hence achieving a proper balance of the engine.
Advantages of the cross-plane crankshaft
- The crankshaft is smooth
- Its performance is vibration-free
- It has a distinctive American car bubble
- They have more torque
Disadvantages of a cross-plane crankshaft
- It is heavier
- Requires a bigger crankcase.
Cars that use a cross-plane crankshaft
The cross-plane crankshaft is commonly used in most American muscle cars like Coyote, LS, and Hemi.
A V8 engine often has one crankshaft, although there are some engines with more than one.
In the V8 engine world, there are only two major types of significant crankshaft designs: flat and cross. In most cases, the cross-plane cranks are used more so in the American V8 engines, while the flat plane crankshafts only show up in full-on race cars and high-end euro exotics.