Slideshow: Flat Plane vs. Cross-Plane Crankshafts
If you’ve ever heard a Ferrari V8 and wondered why they sound so different than a Chevrolet the answer is all in the crankshaft design.
Defining Cross-Plane
Cross-plane crankshafts are what you think of when you think of traditional American muscle cars. Each time the crankshaft turns 90 degrees, one cylinder fires. Because of this design, one bank will fire two times in a row instead of trading off firing left to right in an even manner. This gives the distinct rumbling sound that is opposite the high pitch scream you hear in the latest Italian exotica.
Which is Better?
The answer to which one is better is about the overall package and how well individual parts come together to form a cohesive whole. The new GT350R will have a flat-plane crankshaft like an exotic supercar. Does that mean you can’t put a stock LS6 in a lighter car and smoke it? Absolutely not. That answer also depends on your own ability as an engine tuner as well as the platform you are more familiar with. It’s very similar to cylinder heads when it comes to people arguing about 2-valve vs. 4-valve engines.
>>Join the conversation about flat-plane and cross-plane crankshafts right here on LS1Tech.
Engineering Perspective
Engines have what is referred to as primary and secondary balances. As each can take up pages in their own right, the important thing to understand is that cross-plane crankshafts are balanced and this isn’t some major detriment to performance that a flat-plane crank fixes. Despite what European car enthusiasts might say about these crankshafts —and pushrods— there is no stopping some of the fastest cars in the world from using this design. There are no real drawbacks so to speak of.
>>Join the conversation about flat-plane and cross-plane crankshafts right here on LS1Tech.
All About Feeling
The biggest difference you notice is that cross-plane crankshaft engines like the Z06 have a huge thud of acceleration that rides on a crescendo of torque that European flat-plane V8s don’t have. They are still fast and rev incredibly high, they just deliver the power as the engine revs climb. Traditional cross-plane V8s are brutal and fit the nature of the Z06 perfectly. Let’s hope they are here to stay despite rumors of a new mid-engine C8. Hope you enjoyed reading.
>>Join the conversation about flat-plane and cross-plane crankshafts right here on LS1Tech.
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