Pipe Testing with MYCHRON 2

The Mychron provides an excellent tool for quantitative testing.  We recently had the opportunity to compare two different pipes for our CR-80 and used the MYCHRON in the manner described in the companion article MYCHRON II Data Interpretation.  The two pipes were the RLV/Banke pipe which we have used for a year and a new Superdyne Racing Engines Prototype.

Here is what we did.  First, we ran a handful of laps to get the kart warmed up and the driver motivated.  Then we went out, ran one lap and on the next stopped at the beginning of the straight and did a dyno pull up through the full range of RPM.   Around the track and the same thing again.  Back to the pit, download the MYCHRON and change the pipe.  Repeat the process and head home.  On the home computer, the data export to EXCEL function of the WDRAC software was used to export the four test runs.  We used the MYCHRON HP calculation to generate the wheel HP numbers for export.  In EXCEL, the dyno portions of the data were located and plotted as and XY plot with appropriate scaling.  The resulting plot was copied and pasted into PowerPoint from which the plot was saved as a JPEG so that it could be shown on this document. 

Here are the latest results from March 16, 2001 with a low compression version of our CR-80.

Here are the results of the testing in February with a high compression version of the engine.  Note that this plot includes the MYCHRON calculated wheel HP numbers.   These cannot be directly compared between tests such as the plot above due to differences in gearing, jetting, RAD and other conditions.  This testing methodology is generally only valid for back to back comparisons.

By way of comparison, here is a plot of an earlier version of the pipe.  As you can see, considerable improvement has been made.  The HP and torque calculation for these plots was done in EXCEL directly from the RPM and Speed data, not the MYCHRON calculation.