Background:
Recent data gathering with the Mabotech M520 turbocharger has shown that the stock airbox can be easily modified to operate at 500 WHP and perform similarly to popular aftermarket intakes. (Blaze ATOM vs. Modified Stock Street Comparison).
It is evident that even with a hybrid turbocharger that has a compressor inlet diameter of 60 mm, the compressor housing is a significant factor affecting the turbocharger’s performance, and the intake contribution is much less.
This has led me to search for a larger turbocharger, which would eliminate the compressor housing inlet from impeding air intake comparisons. In discussing the results seen using the M520 with Mabotech, they suggested their M720 turbocharger as a solution for the ‘small compressor inlet‘ issue.
The M720 compressor inlet is approximately 83 mm in diameter compared to the stock IHI IS20/IS38 turbo inlet’s 49 mm diameter.
This turbo ‘should‘ allow me to compare intakes while minimizing the compressor housing inlet and turbo inlet elbow contributions to the pressure losses.
Model development:
With the turbocharger available to pull dimensions from, I made a model of the compressor inlet that could be attached to the flow bench for parts testing.
Most commercial intakes, including those I have on hand, are designed for using a 3″ turbo inlet elbow or stock-size elbow. Because I am unaware of a commercial elbow with a 3″ opening and an 83 mm outlet, I set about creating one that fits on the M720 and connects with the MST Performance turbo inlet hose.
Testing process:
Testing would be straightforward and follow previous intake testing procedures. The commercial intakes would be assembled and attached to the MST Performance inlet hose, and the hose would be connected to the turbo inlet elbow.
The assembled intake system was attached to the M720 adapter, which is bolted to the flow bench. Flow testing would be done at 24″ of H2O.
The products to be tested are:
1. The Racingline R600 closed intake, which is using the Racingline Cotton Air Filter and Foam Filter Sock.
2. The APR PEX open intake.
3. The Blaze Performance ATOM Race V2.
4. The MGM7 Beta 6, an intake I am developing.
Results:
The flow rates measured through the intakes at a depression of 24″ of H2O are shown in the chart:
Conclusions:
There weren’t any big surprises in the results.
The APR PEX and R600 have performed similarly during the previous testing, although in a higher flow rate configuration, the APR PEX showed more advantage over the R600.
Note: The higher flow rate configuration refers to a larger turbo inlet elbow. The 3″ inlet of the elbow used in this test is undersized relative to the 83 mm diameter of the elbow outlet. A 3.5″ inlet elbow would support higher airflow rates, and more difference would show between the intakes. I’m unaware of a 3.5″ turbo inlet elbow; thus, this test was limited to using a 3″ inlet.
The Blaze ATOM Race trails the other intakes, consistent with previous tests where the contribution of the turbo inlet elbow is minimized.
The MGM7 Beta 6 intake handily outperforms the commercial intakes. The difference is greater than I anticipated. I had thought that the 3″ turbo inlet elbow would limit the flow rate to being closer to that of the APR Pex and R600 intakes. This is a good sign that with a larger inlet elbow, the MGM7 will further improve performance over the commercial intakes.