Skydiver pilots do this all day long and they do not use spirals because turning uses up more energy than straight-line climbing. What you should do is look at your sectional and choose a point about 10 miles away, fly there and then come back to the origin climbing the whole time. Lean out your engine as you go so you get max power. On the descent don't forget to use the carb heat, and descend a few miles away from any airport pattern.