Flow Bench and Power Testing

The factory intake system simply can’t match the performance of our intake system. The full factory frontal airbox only flows 521 CFM at 28” of H2O. We improved this by 60% with our open airbox, which flows 833 CFM by comparison! However, it’s important to always look at the intake system as a whole as flow numbers alone don’t always speak to the broader picture. The factory turbocharger can only flow just under 400 CFM through the factory opening, and any intake system will lessen maximum flow. The goal is to minimize all restrictions before the turbocharger as much as possible to maximize performance. The full factory system brings this down to 275 CFM, or 31% less. The full APR System (Open airbox, rear pipe, and turbo inlet pipe), bring this down to 345 CFM, which is only 13% less, or a 25% improvement over stock! This directly translates to more power you can feel. Our full bolt on APR Tuned S3 saw max gains of 12 AWHP and 13 AWFT-LBS of torque using the full intake system compared to stock! These are solid gains that make a noticeable difference in performance!

The Design

The APR intake system features dual frontal inlets which feed to a large airbox. This provides full frontal coverage of all inlets. Air feeds into the airbox, which comes as an open system for maximum flow and sound, but with various optional covers making the system a closed airbox design if you so choose. The covers simply snaps into place without any tools making install and removal simple. Within the airbox is our custom cotton gauze filter. It features a high flow filter material that provides exceptional filtration with very low pressure drop and restriction due to the filters large surface area and an additional frontal inlet scoop.

The filter attaches to the airbox and leads directly into our massive 109 mm (4.28”) turbo inlet pipe. The inlet pipe, which is often overlooked, is typically one of the most restrictive parts of the inlet system. We’ve improved upon this greatly. The cross-sectional area of our system is 99% larger than the factory at the airbox! It connects to the airbox with only a single hose clamp with no need for silicone couplers and adapter. This makes the install simple, and gives the system a very clean and professional look.

Next airflow is directed straight through the intake filter without any initial turns or bends after the filter. The most ideal airpath for maximum performance is a straight through pipe. While not always possible in all situations, every consideration was made to make this system as straight as possible to promote performance. The flow path was optimized with CFD to minimize pressure drop and turbulence within the controlled space. Even the flex section is integrated to allow for necessary movement with low profile ridges for minimal disruption. The system gradually necks down to the turbo inlet adapter. The pipe is oversized to allow for swapping inlet adapters for larger ones in the future for larger turbocharger setups. Once again a single clamp connects to two without any silicone adapters for a clean and easy install with less possibilities for leaks. The turbo inlet adapter features an ideal entrance into the turbocharger and port matches to turbo to prevent any disruptive airflow. Furthermore, unlike the factory inlets pipes, there are no sharp and disruptive bends directly before the turbocharger.

Simply put, this is the ultimate upgrade. We engineered our intake system as a full system because any system that’s designed to connect to any of the factory parts, from the airbox, to the turbo inlet pipe, or the turbo inlet adapter, will have sacrifices in airflow and performance. This is because the system will need to neck down to smaller diameters, or make sharp and harsh airflow disrupting bends.

Performance Gains

To increase power on an intake system you must reduce pressure drop and increase airflow through the system. This allows the turbocharger to work less hard to product the same power, and in the case of many setups this frees up headroom so the turbo can pull in more air and make more power.

We tested the system in various configurations on vehicles with the factory Garret (GTI/A3 Platform) Turbo, and the factory Continental (Golf R/S3 Platform) Turbo. Furthermore tests were conducted with the airbox cover both open and closed. The full intake system was used from the frontal inlets all the way to the turbocharger itself. This is the most true test of the system as it will account for the largest restriction point, which is the turbocharger itself. Lastly, all tests were conducted under the same conditions, on the same day, on the same flow bench, at the same depression.

Continental (Golf R/S3 Platform) Turbo Setups

On vehicles with the Continental Turbocharger (Golf R/S3 Platform) and the with our turbo inlet adapter designed for the factory turbocharger we saw a 39% and 43% increase in airflow in closed and open configurations. However, when upgrading the turbocharger and providing an appropriately matched turbo inlet pipe, the numbers increase dramatically to 66% and 80% in a closed and open configuration at the maximum inlet size! On a Stage 1 equipped vehicle with no other hardware changes or tune adjustments to maximize airflow, the vehicle instantly picked up 15 AWHP and 12 AWFT-LBS of torque! These gains will grow dramatically as more performance mods and larger turbocharger setups are added to the equation!

Optional Covers

The system is designed to be used as an open, or closed intake. If upgrading to a closed system, we offer several options depending on what fits your budget and desired style. The simply snap into place with no tools necessary!

Future Big Turbo Upgrades

This system was designed for the factory turbocharger, but if upgrading in the future, the system can grow with you. The turbo inlet adapter is designed for use with the factory continental turbocharger, but if a larger turbo is used, or if the cover is modified, the turbo inlet pipe can be removed and upgraded to a larger unit. Simply put, this is the only intake system you’ll need as you continue to mod your vehicle over the years!