Supertech K Series Dual Valve Spring and Steel Retainer Combo K24A/K20A Fitment E46 Featuring our unique collar design

Featuring our unique collar design and internal flow structures

the header will sit closer to the ground

This is a MUST HAVE for turbo K swapped cars

calibration uploading and datalogging

Supertech K Series Dual Valve Spring and Steel Retainer Combo K24A/K20A Fitment E46 Featuring our unique collar designSupertech Valve Spring Retainer kits are precision matched sets for a complete valvetrain overhaul. Developed for the performance enthusiast that wants the best the industry has to offer, Supertech Valve Spring Retainer kits are second to none in terms of performance, quality and value. We have trusted Supertech's valvetrain kits on all of our builds from mild to wild. Whether you are running forced induction or a large set of cams on your engine,