Can someone explain to me why this chart is saying the it dropped 45-50 hp with the cat back system????

The dyno chart is from AutoAnything.com

http://a.cdnbrm.com/images/info/magn..._10HP_10TQ.jpg

 

A 45-50 HP drop? When I look at the chart I see a 10 hp/10ft lb gain.

 

Typically when you are reading a dyno graph:

Blue= Stock and Red= Modification

The light bars are the torque values, and the darker bars are the HP values. You match the darker to the left of the graph, and the lighter to the right of the graph, based on the bottom RPMs.

So you are seeing in the 2 light bars, that the torque goes down as the RPMs go up (because our engines make more torque down low) however the Magnaflow exhaust which is light red is a lot higher than stock at light blue. That means the exhaust shows more torque throughout the band.

Then we get to the dark colors, and that's HP. You see both readings go up as you have RPMs, and max out around 5250RPM. However, again the Magnaflow is showing better readings throughout the graph.

I hope that helps?