NgBom, is that an Octo NW-200? If it is, what exactly did you do with your OTP 3000 needlewheel?
I got greedy yesterday, and decided to clip off the top layer of the needle wheel to add more enkamat. As it seems you can't take off the needle wheel with the pins. I then put 3 layers of enkamat on and by this morning I woke up to a pump not skimming. I opened up my pump to see what was going on, and lo and behold, the bottom needlewheel I had left on to attach the enkamat to, was destroyed. Obviously it was rubbing. Do two layers work best?
I also did two more mods. Bored out the intake on the pump, and replaced the 1/4 in. venturi with 3/8 in. venturi.