Mk7 GTI eBay FMIC Minus Stock IC

A third drive was taken with the eBay FMIC this time with the intercooler connected in a strictly front mount arrangement.

Mk7 GTI FMIC - eBay V
Mk7 GTI FMIC – eBay V2


The silicone hoses for this intercooler include branches that attach to the GTI stock intercooler.  For this drive those branched lines were blocked off so that the intake air is routed only through the eBay FMIC.

The route driven was the same as in previous test drives for intercooler performance.

Intercooler Test Route
Intercooler Test Route

Conditions during the drive were slightly cooler than the previous drives, during this test the ambient air temperature was 80 degrees Fahrenheit.  During the prior two test drives the ambient temperature was 87 and 84 degrees F.

Another difference with the previous drives was the engine operating temperature.  For this most recent test drive the engine started at a cooler temperature.


The intake air temperature during this drive is shown on the chart below.

Mk7 GTI eBay FMIC v2 Drive
Mk7 GTI eBay FMIC v2 Drive

A couple of things to point out regarding this drive that differed from the other drives.

  1.  At approximately 300 seconds into the drive a traffic light was encountered that resulted in sitting stationary for about half a minute.  In previous drives this intersection resulted in a decrease in vehicle speed, but not a complete stop.
  2. Because there were temporary plugs placed into the intercooler silicone hose where the stock intercooler would have been positive boost pressure was avoided so as not to dislodge the plugs.
  3. Near the end of the drive the battery charge for the data logging laptop became critically low and the data log was halted earlier than in the other drives.  This was done so that the data would not be lost by a sudden shut down of the computer.

The results from all three of the drives which includes a stock intercooler only, stock intercooler in parallel with eBay FMIC, and eBay FMIC only, are shown in the chart below.

Mk7 GTI Intercooler Configuration Assessment
Mk7 GTI Intercooler Configuration Assessment

The most notable observation from this latest drive is the temperature rise above ambient with the FMIC only in comparison with the other arrangements that included the stock IC.

Prior to the drive I was guessing that the FMIC separate from the stock IC would show and improvement in temperature delta versus ambient as the FMIC has unimpeded external airflow passing through it’s core.  Despite this apparent benefit during a phase of the drive where steady 40 mph driving was held for several minutes the Intake Air Temperature was recorded to be 20 degrees above ambient at the start, rising to 30 degrees above ambient.

Later in the drive when the cruise speed dropped to 30 mph the intake air temperature rose to nearly the same as when the FMIC is used in parallel with the stock IC, an unexpected result.  It was guessed that at low vehicle speeds the FMIC alone would be significantly better than with the stock IC in parallel.


It is inconclusive if operating the GTI with a FMIC and no stock intercooler is beneficial as was postulated.  Test conditions differed from previous tests in terms of ambient air temperature and engine temperature at the start of data collection.

From these findings and trying to account for the different operating conditions it does not appear that using the FMIC alone provides a benefit during this type of a drive.