Why do American race cars sound so different from European race cars
Asked by StevenWicked Jan 23, 2022 at 11:18 PM about the 2021 Porsche 718 Cayman GT4 RWD
Question type: General
7 Answers
Why do performance cars of America sound so different from performance cars of Europe? Long ago when I was young, I raced dragsters and built American performance engines. For the past couple of decades I’ve been involved in SRO track racing where I’ve dealt with European performance cars: Porsche, Audi, Ferrari, and Aston Martin. So being experienced on both, I feel eminently qualified to talk about this subject. Just let me know when I start to bore you….. Exhaust systems for performance cars are designed to enhance engine performance and sound. But the reason why performance cars of those two continents sound so different goes far beyond exhaust. The principal reasons for differing sounds lie in engine crankshaft design and firing order. Long ago, fuel injection vs. carburetion added to that difference, but as carburetors have joined the dinosaurs, I won’t address that here….. Crankshafts in European performance cars are of a single-plane design: literally up-and-down; or 180 degrees. Using a four cylinder engine to simplify this explanation; when you have two pistons at top-dead-center, you have two pistons at bottom-dead-center. In a four-stroke engine, there are two cylinders firing in each crankshaft revolution. These single-plane engines tend to be somewhat out of balance, but they are high-revers, and that makes European racers SCREAM….. American engines, virtually all V8s, use a cross-plane crankshaft design. One plane is driven by four cylinders, and the other is driven by the other four. This design fires four cylinders per crankshaft revolution and they are timed at 90 degrees: one cylinder fires each quarter-turn. This design makes for a smoother running engine that develops higher power & torque, and has a longer life span. These engines have a sound that more resembles a ROAR….. The other principal cause for this sound difference is “firing order.” Most European engines including V and W designs have a balanced firing order: in a European V8, one cylinder fires in one bank and then another fires in the other bank. This causes a smoother, more rhythmic sound. That firing order is more like 1-8-7-2-5-4-3-6 [Odd numbers in Bank #1; Even numbers in Bank #2]….. For some reason, American V8s started out with an unbalanced firing order that resulted in consecutive cylinders firing in each bank. This created problems in exhaust scavenging, and for some reason that seems uncomprehendable to me, they continued using this design. An example of that problematic firing order would be 1-8-7-2-6-5-4-3 (Chevrolet). Notice the consecutive firing in one cylinder bank 2-6, then the consecutive firing in the other cylinder bank 3-1. Some car makers did try to correct this in cars like Corvette and Mustang….. Maybe I should write a book on this? Wait; there are already several of them.
StevenWicked answered 2 years ago
If that firing order was so bad, why did they start using it?
I guess it all began with Ford in its first venture into the flathead V8 in 1932. I guess the cumbersome firing order wasn’t considered a problem in a 65 hp engine that was designed just to get you to work. At the time, race cars were built just for racing. The only streetable cars that raced were insanely expensive exotics, like Duesenberg; nobody ever expected that a common street car would ever be used in competition. But that all changed in the late 1940s when any guy with a few extra bucks could modify a street car for Stock Car or Drag Racing. And in the 1950s, when foreign cars like Porsche and Ferrari started to show up in America, those engine differences started to look more important….. By the late 1960s, this all started to bother me so much that I thought that if had money to burn, I’d manufacture crankshafts & camshafts for Chevy engines that would correct the firing order problem. Then, when the internal modification was done, all you’d have left to do was reposition the plug wires on the distributor….. Well, I can dream, can’t I?
Wow, you have a long and interesting history, Ed. Keep the advice coming!
Thanks, taver91. I'm 74, but I feel about 200. My wife says that's OK, cause I only look 150.
Ed. You're the car guru here. I mean it.
