APR is pleased to present the APR Valve Spring System.
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. We call it Performance Without Compromise!
Key Points:
- Increase valve train control
- 71% weight reduction over OEM Golf R retainers
- 19% weight reduction over OEM Golf R springs
- 20% stiffness increase over OEM Golf R springs
- Eradicates TSI K04 “valve float” issues
- Supports higher revving applications
- Weight saving beehive spring design
- ASTM A877A OTSC round wire steel springs
- 6AL4V American titanium retainers
- 4140 heat-treated chrome molly steel spring seats with 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
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 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 weights 29 grams and represents a 19% weight reduction over the OEM Golf R spring. The result is a highly engineered design that’s simply plug and play!
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 characteristic 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 molly 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 it self, allowing an increased spring rate without negative side effects to the aluminum head.
Eliminating Valve Float
It’s not uncommon to experience valve float with the OEM valve springs, even below the OEM rev limit. On some applications like the 2.0 TSI, backpressure from the K04 turbocharger has been known to force the exhaust valves open. This has been noticed on vehicles with overly weak OEM valve springs and some with higher miles that have simply lost their stiffness over time.
This issue accompanies misfires commonly above 5000 RPM. In some extreme cases, valves are forced open and the vehicle ceases accelerating any further. A quick datalog of intake mass airflow and boost pressure at wide open throttle will show a sudden rise in boost pressure with an immediate loss of airflow as pressure from the open valves is pushed back into the intake manifold.
On other applications, valve float can begin to occur just beyond the OEM rev limit. While other components, such as higher strength valves are often required for extremely high revving applications, the APR Valve Spring System will eliminate float well beyond the revving constraints set forth by the other components.
Returns Policy
Returns are accepted within 15 days of delivery date. Items are not eligible for return if they are: used, altered, damaged, or not in original packaging. All returns are subject to a 20% fee. Special orders are non-refundable. No refunds on electrical parts. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
Part warranties are through the manufacturer only, not Automotive Performance Tuning, LLC(APTuning). Customer is responsible for any applicable labor charges on warranted parts.
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Shipping
We can ship to virtually any address in the world. Note that there are restrictions on some products, and some products cannot be shipped to international destinations.
When you place an order, we will estimate shipping and delivery dates for you based on the availability of your items and the shipping options you choose. Depending on the shipping provider you choose, shipping date estimates may appear on the shipping quotes page.
Please also note that the shipping rates for many items we sell are weight-based. The weight of any such item can be found on its detail page. To reflect the policies of the shipping companies we use, all weights will be rounded up to the next full pound.