Ecotec Exhaust & Airflow

GM Ecotec exhaust valve size guide covering stock diameter, stem size and common L61, LAP, LE5, LE9, LSJ and LNF applications. Compare OEM and performance valve sizing and learn why...

Do performance Ecotec exhaust valves actually increase airflow? See what BK Racing learned from back-to-back flow-bench testing, including how an intentionally undersized development valve gained 3 CFM over the stock...

Stock vs Performance Ecotec Exhaust Valves: What Actually Changes? When comparing stock vs performance Ecotec valves in a GM Ecotec engine, the first specification most people look at is valve...

The complete guide to GM Ecotec exhaust valves for L61, LAP, LE5, LE9, LSJ and LNF engines. Learn how OEM and performance exhaust valves differ in size, material, airflow, geometry...

Two Ecotec engines. Same cams. Same cylinder head. Same exhaust system. Different headers. One makes more power. The other doesn’t. Why? The answer lies in scavenging, exhaust velocity, collector design,...

Can a true long tube header fit a Chevrolet Cavalier or Pontiac Sunfire? The answer surprises many Ecotec enthusiasts. From engine mount positioning and tunnel clearance to thermostat housing modifications,...