On my way into work this morning, I was curious what my onboard accelerometer dyno was showing my peek HP #’s at. After my engine & transmission got up to operating temp, I put it in track mode and watched the HP readout on my dash DIC, and also set the performance pages to the dyno graph. I saw the HP # on my DIC flash 6XX before it shifted and the dyno graph confirmed the 600 HP I saw once I paused it.
This got me thinking about the differences people have been seeing in these HP #’s.
Here are the things that I think are contributing to the discrepancies we are seeing:
Elevation
Outside ambient temp
Humidity level
Fuel Octane level used
How long the engine has been run. (Is it heat soaked or not)
List any upgrades. (intake, exhaust, tires, etc.)
This morning has been the coolest morning (@ 72*) we have had since I purchased my TH.
My Elevation = 1300 Ft
Temp= 72*
Humidity = 74%; Dew point = 70*
The highest octane fuel I can buy here is 91.
Engine just brought up to operation temp. Coolant = 200*; Engine Oil = 180*
All stock.
According to the elevation calculator below, @ 1300 Ft elevation I am losing around 28 HP at the crank when compared with sea level output.
http://www.wallaceracing.com/braking-hp.php
All things being equal, I think we should be asking these questions when someone is posting higher than “normal” HP #’s. It would be hard for me to believe someone got a hellcat motor that is producing ~80 more HP than another one…. This is just my 2 cents.
Disclaimer:
***Remember the onboard accelerometer dyno is not measuring the engine HP output at the crank, but rather measuring the HP it “sees” being put to the pavement using an accelerometer dyno. Even the HP to the pavement #’s can be questioned and is more of a ballpark #. The only way to know for sure is to use the same all-wheel dyno at the same time and place with the same fuel. ***
