RE: engine mod and paint question
If there is a local hobby store that carries lots of R/C items, you should be able to find narrow trim tape there. Any automotive store that carries auto paint supplies will also have what ya need.
Pipe'n a motor will gain you some speed, but the real deal is in prop work. Learn how to work on props, best bet is to get several x440 and make each different. Cupping, Texas cut, back cutting etc will gain the most speed for the buck. There are other props that will get you speed (prather 215, x1440, etc), but the x440 is an all around good prop for the K&B 3.5 motor. Don't be surprised if that Prather boat gets too wild with the mods you plan. That is a very old design compared to current models out now.
I've got a 29" WOF with a .21 MAC (heat racing mods from CMDi) and Lawless Quick Shot lower unit. With a stock prather S215, it was radar'd at 44.7. I've already changed the S215 and have a few others on the way here for more testing. I'm hoping to get up into the mid 50's with different props.
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