I will be the last one to tell you thats not possible with a .18, I'v done it and then some (but with a bigger prop),, I will say it's a little on the high side for a Y535prop, that TZ had to be SCREAMING with that small a prop.
Where did you have the GPS Mounted???

Wish you were taking Vids and Not Pics of it,,,LOL,, I always love to see a fast .18 Hydro vid[8D].