Blaze Performance supplies several intake options for the Mk7 GTI. A fellow enthusiast pointed out to me some of the products they offer and I was particularly interested in the inlet pipe, specifically the adapter/inlet flange that connects the inlet hose to the turbocharger.
The inlet elbow plays a large part in how well an intake system flows. Previously the similarly designed Revo inlet hose has been flow tested and while it performed well, I thought there might be some room to improve on the design. The Blaze Performance inlet flange appears to incorporate improvements compared with the Revo model.
Blaze Performance offers several variations of the turbo inlet hose, for this flow test the 3″/76mm Turbo Inlet Hose is being used. They also supply a larger 100mm/4″ inlet hose as part of the AToM induction kit as well as the R600 upgrade kit.
Note: Blaze performance offers left-hand drive and right-hand drive hoses.
During the initial checkout of the parts, I mentioned to Blaze that I thought the inside diameter of the flanged outlet, at 56mm, might be larger than necessary and may be a detriment to airflow. The IHI turbocharger inlet of the compressor housing is ~49mm.
Blaze Performance informed me that they had been considering including an insert to the intake kit that would reduce the diameter of the outlet for use with stock-size turbocharger inlets. Their intake flange is sized to work with larger hybrid turbochargers, but my standard test is with a bench adapter that is the size of a stock turbocharger inlet.
Blaze sent a stereolithography (STL) file of the insert so that I could 3D print a model to use in testing.
This insert provides a smooth transition to a diameter matching the stock turbo inlet.
Before measuring the flow rate through the intake components the flow bench is first checked to ensure the measurements will be accurate.
The printed insert is installed in the turbo inlet hose metal flange.
The Blaze flange is then inserted into the inlet hose and secured. On the other end of the hose, the top half of a stock GTI airbox is attached. This is done to help direct air smoothly into the intake.
The inlet hose flange is inserted into a fixture that simulates the compressor inlet of the IHI IS20/IS38, and that fixture is attached to the flow bench.
Measurements of airflow are made with the left-hand and right-hand hoses at a depression of 28″ of H2O.
Next, the insert is removed from the Blaze Performance inlet flange and the flow bench adapter is substituted with a straight coupler silicone hose. This hose is meant to simulate a larger turbocharger that may have a larger compressor inlet.
This silicone hose variation has been used occasionally in previous tests.
The Blaze Performance turbo inlet hose is attached to the flow bench and airflow measurements with the straight silicone hose are recorded.
Flow test results using the left-hand and right-hand hoses are:
- Left-hand drive: 404 CFM @ 28″ of H2O
- Right-hand drive: 414 CFM @ 28″ of H2O
These results are shown on the chart with some other turbo inlet elbows that have been tested using an aftermarket turbo inlet hose.
Note: Some turbo inlet pipes have only been tested using the stock accordion hose and those are not included on this chart.
Flow measurements of the Blaze Performance turbo inlet pipe attached to the silicone coupler are:
- Left-hand drive: 510 CFM @ 28″ of H2O
- Right-hand drive: 545 CFM @ 28″ of H2O
Other turbo inlet pipe setups that have been tested using this larger fixture are shown along with the Blaze Performance products on the chart:
The Blaze Performance 3″ turbo inlet pipe and intake flange attachment for the Mk7 GTI were flow tested. Left-hand and right-hand drive models were tested.
The right-hand drive hose flows higher than the left-hand drive hose. This apparently is a result of shallower bends.
Attached to the flow bench using an IHI compressor housing size adapter the Blaze Performance turbo inlet pipe flow is comparable with other aftermarket inlet pipes that have been tested. The left-hand drive hose flows on the low end of products tested and the right-hand drive version flow rate is at the top end.
Attached to a silicone hose to simulate a larger/hybrid style turbocharger compressor housing the Blaze Performance products flow rate is on the upper end of the products tested. The left-hand drive version is in the top half of products tested and the right-hand version is the highest flowing setup that has been tested, the measured flow rate is 3.4% greater than the previous top flow rate.
Note: The inlet flange insert produced a 4% increase in flow rate when using the IHI size adapter when compared to the setup without the insert. Airflow for both hoses increased ~ 15 CFM when the insert is installed.