White Dog Racing IC Inlets

In addition to the White Dog Racing Bipipes that I flow tested a couple of days ago the box contained a set of the intercooler inlet pipes that replace the stock components for use with the Silly Rabbit Motorsport RS4 side mount intercoolers.

Picture of White Dog Racing intake parts
White Dog Racing intake parts

These inlets in addition to being made of metal are larger in diameter than the stock components they replace.

For the flow testing I attached the inlet to the SRM intercoolers and mounted them onto the flowbench.  I began with the stock hardpipes and couplers supplied with the SRM intercoolers.

SRM Stock Inlet Pipe
SRM Stock Inlet Pipe

Both the driver and passenger side flow performance was measured.

Then I swapped to the White Dog Racing inlet pipes and checked the airflow again.

White Dog Racing Inlet (Driver side)
White Dog Racing Inlet (Driver side)
White Dog Racing Inlet (Passenger side)
White Dog Racing Inlet (Passenger side)

 

Finally, for comparison with a completely stock setup I used the stock S4 intercoolers with the stock inlets.

Stock S4 components
Stock S4 components

Results:

Airflow through each of the setups was measured at a depression of 28″ of H2O.

Inlet Pipe Flow Test Results
Inlet Pipe Flow Test Results

The chart above illustrates a number of pieces of data:

  1. The red bar and purple bar are the airflow readings from a stock intercooler and the SRM RS4 intercooler – without any inlet piping attached.  It is clear that in this configuration the SRM RS4 IC greatly outflows the stock intercooler.
  2. The green bar shows the reduction in airflow through the stock intercooler when the stock inlet piping is attached.  There is a modest decrease in airflow as compared to the IC alone.
  3. The orange and blue pair of lines are showing driver versus passenger side results of swapping inlet pipes between stock and WDR.  The passenger side has a higher airflow for each pipe arrangement.  Their is a small improvement in airflow when switching from the stock to WDR parts. (It should be pointed out that readings taken under operating conditions would be different as charge air under boost is denser and thus develops more back pressure).
  4. Finally, the SRM RS4 intercooler undergoes a substantial drop in airflow with the addition of the inlet piping, regardless of whether it is stock piping or the WDR piping.

Conclusion:

The airflow through the intercooler and inlet is increased measurably, but only slightly, by using the larger White Dog Racing hard pipes, when evaluated on the flow bench.

For a typical user the larger inlet pipes may not provide much performance benefit, but for the all-out build where optimizing every part matters, the White Dog Racing hard pipes do provide measurable gains.

Solo shakedown drive

Things progressed this weekend with the TTE550 turbochargers, but it’s been a bittersweet continuation of the project with the sudden unexpected passing of “Daz Dillinger”.  Daz is a person with whom I have partnered on several projects since we were first introduced several years ago.  It has been his knowledge and generosity that have provided the foundation upon which this project, as well as others, have been built.  I will have more to say about Daz’s work with me in a separate posting.

The first drive with the TTE550’s has been successful, although with two issues to address.  First was a high pitched siren sound when boost hit about 20 psi, something I immediately thought was a boost leak.  After hooking up the boost checker I confirmed my hunch, that yes there was a hose clamp on the upper passenger side intercooler that was not tight enough.  It was a relief to have the problem be located in such an easily accessible location.

The second issue, which is a known obstacle to overcome with the changing out of turbochargers, is that the TTE550’s use an 8 psi-preload on the wastegates, and the FT21’s used about 14 psi.  Thus the tune now will under-boost on account of the wastegate differences.

TTE550 First Boost Log
TTE550 First Boost Log

 

White Dog Racing Intake Parts

A box full of White Dog Racing intake parts for the Audi B5 S4/RS4 has arrived for flow testing on the PTS flowbench.  The parts, shown below, consist of a few variations of the intake bi-pipes and a set of turbocharger to intercooler hardpipes.

Picture of White Dog Racing intake parts
White Dog Racing intake parts

The intake bi-pipes cover the 54mm and 60mm tube diameters, flowing to a stock throttle body.  Within the two 54mm size pipes there are two variants, one with the MAP sensor in the stock location and one with the sensor offset.

The IC inlet pipes are intended for use with the Silly Rabbit Motorsport SMIC’s with the larger RS4 size piping.

Results:

After adding the APR bipipe and RS4 bipipe into the mix I began setting things up for testing.

Bipipe Lineup
Bipipe Lineup

One thing I noticed right away was how much lighter the White Dog Racing bipipes felt in comparison to the APR bipipe.  I set each product on a postal scale to get an idea of the relative weights.

  • APR: 5lb 9 oz
  • WDR-60: 2lb 9oz
  • WDR-54: 2lb 7oz

Those weights are approximate as I needed to balance the products on the scale, and I did not bother to remove the MAP sensor, DV hoses, or WMI nozzles/line from the APR bipipe, but the general trend is clear, the APR bipipe weighs about twice what the White Dog Racing products weigh.

bipipe_lineup

I also made a comparison of the inlet diameters:

bipipe_intakes

In sequence from smallest diameter to largest:

apr_bipipe_inletWhite Dog Racing 54mm BipipeWhite Dog Racing 60mm Bipipers4_bipipe_inlet

Then it was on to the flow bench:

White Dog Racing 54mm Bipipe on Flowbench
White Dog Racing 54mm Bipipe on Flowbench

 

A comparison of the results is shown below:

White Dog Racing Bipipe Flow Testing
White Dog Racing Bipipe Flow Testing

 

Some comments on these results.

  1.  The White Dog Racing bipipes performed surprising well given the use of the stock S4 throttle body.  The larger RS4 components only flowed slightly more than the WDR products.
  2. I am especially impressed by the 54mm WDR product.  Enlarged aftermarket parts often pose a challenge to fit into the S4 engine compartment.  It’s likely that minimal accommodations would need to be made with this pipe yet the airflow increase over stock components is substantial.
  3. The similar results measured from the RS4 components and 60mm WDR bipipe has led me to further consider the benefit of the RS4 throttle body.  These results appear to show that the stock TB is not much of a limitation on airflow with these size bipipes.  If that is the case then the effort to have an RS4 size throttle body attached to S4 intake manifold, like the SRM product that I have on hand, may not be worth it.
  4. The difference in airflow between the two WDR-54 size bipipes was minimal so I averaged the two measurements to present a single value.
  5. The stock bipipes were not measured at the same time as the other bipipes.  Due to potential differences in test conditions, ie equipment setup, bench calibration, atmospherics, it is possible and likely that the stock bipipes would have performed differently had they been available.  Comparing the RS4 and APR bipipes to the results recorded a few years ago when the stock pipes were tested showed those two products with a calculated airflow 7-10 CFM greater than what was recorded/measured today.  Thus it is likely that the stock bipipe datapoint slightly overstates the airflow under today’s test conditions, I estimate by 5 CFM, but it should be close enough for a general comparison.
  6. The relatively lower airflow through the APR bipipe meant that I was able to measure it at 28″ of H2O, whereas the other products were measured at slightly lower depressions.  The reason for this is that the internal plate on the flow bench is spec’d to approximately 600 CFM and the other bipipes tested were able to reach that limit.  In order to standardize the results all measurements were adjusted to a 28″ H2O depression.  This adjustment was minor – the RS4 bipipe was flowed up to 24″ and the WDR bipipes flowed to 26″.

Below is the percentage increase in airflow that is gained from using the alternative bipipes.

White Dog Racing Flow Increase

In terms of airflow performance White Dog Racing has debuted an impressive product that gives a solid alternative to the hard to find RS4 components and a substantial improvement over stock parts.