Engine Building

Does your Ecotec need cylinder-head modifications for upgraded valve springs? Learn the difference between drop-in and modified spring systems and when machining, retainers, seals, or spring-seat changes are actually necessary.

Does a performance Ecotec really need dual valve springs? Learn how single and dual springs compare in pressure, spring rate, lift, dynamic control, installation and high-RPM performance.

Higher RPM gives an Ecotec valvetrain less time to complete each valve event. Learn how engine speed increases spring demand and why RPM must be matched with camshaft profile, valve...

Coil bind isn't the only limit on Ecotec valve lift. Learn how retainer-to-seal clearance, valve guide clearance, spring seats and retainers determine the usable lift of a performance Ecotec cylinder...

Do Ecotec balance shaft deletes really cause excessive vibration? Learn how the factory balance shafts work, what changes when they’re removed, and why real-world customer experiences often differ from internet...

Can you delete the balance shafts on a street-driven GM Ecotec? Learn the pros and cons, how a balance shaft delete affects vibration, reliability, and drivability, and whether it's the...