Originally Posted by Maximo

what pipe are you guys running ? 2 chamber or 3 chamber ? this can make a huge difference.. Are you using INS boxxes ?

now when you say modified and stock , would you consider removing head shims modifying ?

Power and efficiency are closely tied and often times when engine is making its best power its also running most efficiently ..when we start forcing less then ideal conditions on the engine you will start to see a reduction in fuel economy .. Does your daily driver get better fuel economy with a partially clogged air filter ? 2 strokes are funny and I am finding that when I hit the magic spot power wise on a modified engine we are also seeing extremely good runtime as well....now what has to be taken into account here is that when a engine is making more power it is also capable of doing more work, which can change the runtime.... what I am getting at here is that comparing runtime between a fully modded 9 port on a 9mm against a choked back 5 port may not give the full picture...the modified fully opened up 9 port can be getting better efficiency but doing more work in the same amount of time as the less efficient 5 port , so their final runtime looks the same ..meanwhile the 9 port is cutting faster laps and hitting 4 MPH higher down the straight....

I am fully willing to dyno test any combo someone wants me too...just let me know the engine and pipe, or send me your engine and pipe...