This post updates the continuing test and evaluation of turbocharger inlet elbows available for use with the Mk7 GTI/Golf R.
Burger Motorsports supplied one of their inlet elbows, shown below:
Also available for this round is an inlet elbow from MST-Performance who contacted me and offered to provide their inlet kit which consists of both the inlet elbow and hose that connects the airbox to the inlet elbow.
The MST elbow deviates from the test configuration that has been used up to now because of the use of the inlet hose. The reason for the use of this hose is that the intake side of the elbow is wider than the stock accordion hose. The stock hose outlet will fit inside the MST elbow intake inlet.
With the test items collected the flowbench was run through a calibration check.
The inlet and outlet cross sectional diameter of the Burger Motorsport elbow and MST-Performance elbow were measured; results are shown below along with previously measured products:
Inlet / Outlet diameters (mm):
- APR – 62.7/48.7
- BMS – 66.2 / 53.9
- MST – 72.4 / 48.1
- Stock – 61.9/47.6
- Unitronic – 64.7/48.7
As with the previous Round One of tests the inlet elbows will be attached to the stock airbox upper half for the flow test.
Up first for testing is the Burger Motorsports inlet elbow.
Peak airflow measured approximately 482 CFM @ 28″ of H2O.
Next to be tested is the MST-Performance elbow and inlet hose:
Peak airflow measured 495 CFM @ 28″ of H20.
Combining the latest measurements with those from the previous test produces the chart below:
The increase in airflow that was measured through the Burger Motorsport inlet elbow is substantial, and was surprising. Looking at the piece beforehand I had some concern about the transition at the outlet because it necks down slightly.
Clearly the concern was unfounded because the Burger part flows roughly 32% more air at the test point when compared with the stock inlet elbow. It was also a surprise to see the gains versus the two previously tested elbows from APR and Unitronic, both which have very smooth inner walls. Perhaps the larger cross section of the Burger part at the inlet and outlet contributes significantly to the airflow performance in this test.
The MST-Performance part introduces an interesting mix of design considerations for maximizing airflow through the intake, the result was a 36% increase over the stock setup, the greatest airflow gains measured thus far.
A couple of observations about the MST-Performance inlet; it has the largest inlet of the products evaluated thus far, but the outlet is smaller than both the Burger and Unitronic elbows. The MST-Performance elbow uses a larger inlet hose than any product tested to this point.
A possible future test will be to connect the MST inlet elbow with the stock accordion hose, if possible, to estimate how much, if any, difference the MST inlet hose makes on the airflow results.