I had posted this earlier =
Originally Posted by Christian.
I will load the VF39 vehicle on the same dyno tomorrow and report back to you guys. I need to let you know that the we have two chassis dynos and the one we originally developed the VF39 mapping on is down for servicing. The dyno will most likely read a bit differently because they run different software and they are two different (same MFG and model #, but different units) dynos...which is why the other dyno is down right now. We are upgrading the software and servicing the bearing right now. Regardless, what you want is an FP18G/VF39 comparrison on the same dyno and that is what I will try to post by Friday of this week.
Here is some additional information about both of our chassis dynos. Both of our chassis dynamometers are very accurate. One is not more accurate than the other. One was just running a version of software that is much newer, the older chassis dyno was one of the first ones in America. This is why I am currently servicing and upgrading the older dyno to the newer software. Just an FYI, the SAE also changes how HP is measured and most dyno manufacturers do not keep their clients up to date with these changes. This is one of the many reasons we use Mustang Dynamometers...they constantly update and improve their software. Regardless dyno #1 will always read differently (very, very slightly now that they will be running the same software) than dyno #2 because they are two different dynamometers with different parasitics, static weight, etc. I have spent the last several months preparing the new dyno room and dyno #2 so that all of our tests will be performed on the same dyno from now on. This new dyno software allows me to datalog 2 separate EGTs, 2 separate intake air temperature sensors, relative pressure (boost), exhaust gas back pressure, WBO2, RPM, speed, etc. along with the torque and horsepower curves. I used this new software feature to graph the boost and Lambda (Air/Fuel) curves for the 2006 WRX MT VF39 map notes. I wanted to better represent how boost should be responding, rather than just typing the boost target and the taper values. Plotting the fuel curve has been very helpful as well. These particular tests just happened to come when I was servicing dyno #1. My guess was that our clients would appreciate that the release of these maps was not delayed…I hope I was correct with that assumption. In addition, all dyno #s will change over time because dynos are like vehicles, they wear down, they need maintenance, parts break and need to be replaced, etc. Long story short, chassis dynamometers are just tools used to measure differences, positive or negative, in performance. With this new mapping we were able to make significant improvements on the 2006 WRX MT using the VF39 and FP18G turbos. I hope you enjoy the new mapping. I will be paying attention to this thread, I want to make sure I answer any questions you all may have.