HTP/PLA Hybrid - Oxidizer Rich

In an attempt to increase the thrust of the class I engine, I increased the O/F ratio by shortening the fuel grain from 15 cm to 12.5 cm. This reduced the contact surface area of the fuel grain and also, reduced the mass of the rocket engine by about 20 gm. Ignition occurred around 0.9 sec. I observed a net positive thrust of greater than 19.1 N at ignition and a c* efficiency of over 100%.