Does anyone know exactly why Harley uses cross-over exhaust. I put Rinehart true dual exhaust on my 03 and had an ECM download done; I did not really see any difference in the engine performance. I am trying to decide what to do with the new 08.
dalwolf,
Exhaust system "crossover" pipes can actually serve more than one purpose. In the case of a stock exhaust system, the crossover allows the cylinders to share muffler volume, which helps reduce noise levels without adding excessive restriction or going to much larger mufflers.
A properly designed crossover system will also enhance performance by balancing exhaust flow variations due to engine firing order (more of an issue on engines with more cylinders, like a V-8 auto engine), increasing the exhaust scavenging effect, and reducing reversion. A good example of a really good system can be found under your typical NASCAR stock car. Unfortunately, the crossover on an FLHT doesn't remotely resemble the performance enhancing types that can be found elsewhere.
Jerry
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Topic: Cross-over Exhaust (Read 1045 times)