The Scavenging Effect · Help Center - Summit Racing
The Scavenging Effect Definition and Description Scavenging occurs when the rush of exhaust gas leaving the cylinder helps to pull in more fresh air (and fuel). How does it work? During the exhaust …
Exhaust Runner Volume · Help Center
Tuning runner length to promote Exhaust Scavenging. Tuning runner diameter to maintain flow velocity without restricting flow volume. Exhaust runner volume is far less important than the Intake Runner …
Exhaust Reversion · Help Center
Definition and Description Reversion happens when exhaust gases flow backwards and contaminate the intake charge. (It is the opposite of The Scavenging Effect.) What causes it? Backpressure in the …
The Header Collector · Help Center
Scavenging is created by maintaining the speed of exhaust flow. When the high-speed pulse of exhaust from the primary tube reaches the larger collector, it slows down.
What is valve overlap? · Help Center
At high rpm, overlap takes advantage of the Scavenging Effect. However, at idle and low rpm, overlap will produce low Engine Vacuum and a rough idle. This is great for a race car, but not so much for …
How do I choose a set of headers? · Help Center
The pulses of exhaust gases in the primaries also create a Scavenging Effect in the cylinder. This improves airflow through the engine and can free up plenty of ponies! Before buying a set of …
How do valve timing events affect engine performance?
Valve Timing Events Explained Knowing what Valve Timing Events are and how they affect performance will help you understand what to expect from your cam. Valve timing events set Duration, Lobe …
What are the Four Strokes of an Engine? · Help Center
A Basic Overview A single stroke in an engine refers to the piston traveling the full sweep of the cylinder. There are 4 strokes in an engine's cycle. They are Intake, Compression, Power, and Exhaust. One …
Should I wrap my headers? · Help Center - Summit Racing
This improves exhaust flow and The Scavenging Effect. It also lowers underhood temps. Wrapped headers will make a little more Torque and Horsepower than a bare metal set. Despite improving …
Advancing / Retarding a Camshaft · Help Center
A Basic Overview of Cam Timing To advance or retard a camshaft is to change the alignment between the camshaft and the crankshaft. When a cam is installed "straight-up," the imaginary centerlines of …