Oil content will remain the same. Sometimes when going to a higher nitro fuel you do have to open up the needles SLIGHTLY, more power, more fuel. If its anything like mine it will not be sluggish at all with the 16 x 4W and 30%. Now when I tried it with 15% that would be a good description.

That said, the 15 x 4W and 20% makes for a good combo on the UCD 60.

Ed M.