2012-2013 Audi TT RS Set of 20 Valve Springs, Seats and Retainers by APR Tuning
The APR Valve Spring System is a high-performance, lightweight upgrade designed to increase valve control and eradicate valve float common on many applications. APR's design specifications called for a valve spring, retainer, and spring seat combination that doesn't overpower and snap the OEM valves or erode the aluminum spring seat, while still maintaining exceptional valve control. The result is an advanced design that's 28% lighter yet 20% stiffer than the high-performance OEM Golf R setup and is proven to eliminate the OEM valve train's weakest link.
Valve Springs: Weight reduction, and not necessary stiffness, is absolutely necessary to increasing valve control. The APR Valve Spring utilizes a beehive design that allows for a reduction in mass in not only the spring itself but also through the use of a smaller titanium retainer. The springs feature an ovate wire design that allows for even stress distribution resulting in better control at high RPMs through a resistance of harmful valve float inducing harmonics. The lightweight design also accomplishes accurate valve control without requiring an overly stiff spring which has been proven to snap OEM valves in half. Each valve spring weighs 29 grams and represents a 19% weight reduction over the OEM Golf R spring.
Valve Spring Retainers: Through the use of a beehive design, APR's Engineers were able to design and supply a valve spring retainer that's smaller than stock to reduce weight as much as possible. In an effort to offer extreme weight savings, at an additional 71% over the OEM Golf R retainers, American 6AL4V titanium was used for its high specific strength weighing in at only 2 grams each. By offering outstanding weight savings, exceptional valve control characteristics are achieved while only requiring a modest 20% increase in stiffness over the OEM Golf R spring.
Valve Spring Seats: Often an overlooked piece of an upgraded valve train is the valve spring seat. The factory heads are aluminum and unfortunately increased spring pressure can distort or erode the mating surface overtime as they mate directly to the bare head. To prevent this from happening, APR's Engineers designed valve spring seats out of 4140 heat-treated chrome-moly steel with a black oxide coating. The spring seats are strong enough to withstand pressure from the springs and provide a mating surface that evenly distributes spring load across a larger area than the spring itself, allowing an increased spring rate without negative side effects to the aluminum head.
Features
- Weight saving beehive spring design
- ASTM A877A OTSC round wire steel springs
- 6AL4V American titanium retainers
- 4140 heat-treated chrome-moly steel spring seats with a black oxide coating
- 29 grams per spring
- 2 grams per retainer
- Compatible with OEM valves
- Spring seats included to protects against aluminum erosion in the head
Benefits
- Increase valve train control
- 71% weight reduction over OEM TT RS retainers
- 19% weight reduction over OEM TT RS springs
- 20% stiffness increase over OEM Golf R springs
- Eradicates TSI K04 "valve float" issues
- Supports higher-revving application
