I attached the WDR FMIC to the flow bench again, this time using a thick piece of plastic to cover one of the inlets and then sliding the coupler hose over the plastic to hold it in place and form a seal.
Then with just a single inlet open I tested the intercooler again.
I was a bit surprised by the difference in airflow readings between the two halves. The passenger side is flowing approximately 14% more than the driver’s side.
Each half of the core has the same number of charge rows, 17.
Based on the physical appearance of the cores the only immediately obvious difference that I would guess to be causing the difference is the longer exit path that the air from the driver’s side flows through on the top side of the cores prior to exiting the FMIC.
After numerous failed efforts over the years to get a hold of a Front Mount Intercooler for flow testing, White Dog Racing sent over their product, which arrived today.
Numerous bungee cords were recruited to hold it above the flow bench for the testing.
The results of the flow test are:
The red bar shows the airflow through the FMIC core without the inlet hump hoses attached.
The pattern when adding the hoses to the inlets has been for the airflow through the core to increase, that was the case with this FMIC as shown by the blue bar
This setup is not very appropriate for comparing with the SMIC’s that I have previously tested since the SMIC’s were tests of a single core, and the SMIC cores were attached straight to the bench, where this FMIC required the elbow silicone coupler to attach to the bench.
The obvious next question after seeing the FMIC result is “how does that compare to the SMIC’s?” I have included the highest flowing single SMIC that I have tested on the chart, the SRM SMIC, but it should be understood that this comparison between FMIC and SMIC is far from ideal.
All of the turbochargers I have had my hands on lately have been put on the flowbench to have the airflow through the turbine housing recorded.
The most recent B5 S4 suitable turbocharger to show up is a pair of the Audi RS6 K04 turbo’s. Because in OEM form these will not fit on the 2.7T engine this pair has been modified to work with B5 S4 components.
Unlike with the TTE turbo’s that also showed up with turbo to downpipe studs firmly stuck in the turbine housing, I chose not to pay a shop to remove the studs out of the RS6 turbo’s turbine housing. Instead I’ve modified the adapter used to attach the turbocharger to the flowbench to accommodate the studs.
Following alteration of the adapter I went through the normal process of testing an article on the flowbench, beginning with a calibration test. Results of the flow test are shown below:
It is clear that the airflow through the RS6 turbine housing is substantially greater than of that through the RS4 K04 and FrankenTurbo F21 turbochargers. (The F21, TTE550, and TC Stg1 flowed approximately the same so I have omitted the TTE550 and TC Stg1 data from the chart to make following the lines easier.)
I have found the results on the flow bench to correlate with the exhaust back-pressure readings that I have made on my S4. That the RS6 K04 turbocharger is able to flow higher than RS4 K04’s comes as no surprise, the magnitude of the increase is the most noteworthy finding from this test.