RE: GP Shoestring
If you want speed--then put a 2-stroke 90--100 on it and use a high pitch prop.
You are running a 4-stroke with a 6 pitch prop. I'm not surprised that your unhappy with the speed.[sm=lol.gif]
Put a ST90 on it and use a 12-10 prop. That should put a smile on your face.[sm=thumbup.gif]