XS-Power Bipipe Flow Test

An XS-Power bipipe was delivered a few days ago to go into the Get Healthy Silver S4 that I’m currently working on.   Since the product has not been flow tested, and this one is available, I decided to stick it onto the flowbench and see how it performs.

XS-Power Bipipe on Flowbench
XS-Power Bipipe on Flowbench

The XS-Power bipipe intake diameter is 51 mm on the inside of the pipe.  Here is how this compares to the other alternative bipipes I have measured the inlet size of:

  • APR:  49.8 mm
  • WDR-54:  52.4 mm
  • WDR-60:  59.3 mm
  • RS4:  61.1 mm

I tested the XS-Power Bipipe with a Stock B5 S4 Throttle Body at 28″ of H2O and recorded a CFM of 545.  This compares to some of the other bipipe options as follows:

XS-Power Bipipe Flowbench Test Results
XS-Power Bipipe Flowbench Test Results

Peak airflow ranking correlates with the inlet diameter, the XS-Power bipipe places just above the APR bipipe and a little below the WDR-54 bipipe.

With the APR bipipe being discontinued the XS-Power bipipe presents a new option that is similar in design as well as performance.

In the past I’ve noted that different results occur when the inlet hoses are connected to the bipipes.  The comparison above is using just the bipipe without an inlet hose.

To illustrate how the inlet hose alters the airflow through the bipipe a comparison with and without the inlet coupler hose is shown below:

XS-Power vs APR vs Stock Bipipe Airflow
XS-Power vs APR vs Stock Bipipe Airflow

The APR bipipe shows the greatest increase in airflow with the coupler hoses attached, having a maximum airflow equivalent to the XS-Power bipipe within the measurement margin of error.  All of the bipipes see a reasonable gain in airflow when the Intercooler coupler hose is attached to the end of the bipipe.

Get Healthy Engine Out

Today the engine came out.  Detaching the driveshaft from an S4 that has never had the driveshaft disconnected before is fun, boy those bolts are in there good.  The driveshaft is also well attached to the transmission, even without the help of the bolts.

CP B5 S4 Engine Out

I tried something different this time to free the driveshaft from the transmission.  I put the car in gear, raised the driver side rear wheel and gently rocked the wheel back and forth until the driveshaft popped free from the transmission.  Much easier than laying under the car trying to pound the driveshaft free.

I was extremely pleased to have almost no coolant loss when removing the heater core hoses, there’s been times in the past where this part of the removal has produced a big mess on my garage floor.

Audi B5 S4 transmission removed
Transmission Removed

Project Get Healthy

To make room for the built engine in the Avant it’s stock engine needs to go somewhere, that somewhere is this Silver Sedan.

Audi B5 S4 Sedan
Audi B5 S4 Sedan

Today I began taking the Silver S4 apart in preparation for the swap.