Big bore engines are all about the flow, more air in and more air out, anything that slows that down, robs horsepower. The factory M8 intake manifold does a decent job in stock form but starts getting in the way when trapped between 124" and larger cylinders. The stock polymer unit is also less tolerant of the additional heat that a big bore engine can make at full noise. The solution is the new S&S high flow cast aluminum manifold and a must-have for top-level performance in the M8 platform Adds 3-5 Hp with a simple bolt-on install and fits most M8 models (Softail and Touring) from 2017 to 2021.
The S&S High Flow Manifold is priced at $189.95 and available through your local dealer or directly from S&S Cycle. Check out the details as well as the collection of performance parts for this machine on the S&S site or hit up your local dealer for more info.