For the week of 2/23 – 2/27, we executed another compression check in order to compare it to the old results. The average compression in the cylinders this time around was 205 psi, while in the past test the mean was 220 psi. This drop in pressure is nothing to be worried about because we are still well within the range of compression specified by the manufacturer. More important is even compression between cylinders. If the lowest cylinder is more than 20% less than the highest cylinder it can cause the engine to run rough, but the lowest cylinder again is No. 5. by only 6%.

Because the check did not take too long to do, we also worked on identifying what tools we are going to need for our parameters and their location. Thermocouples are going to be used for the temperatures of the exhaust and radiator, while a sensor is going to be purchased for the mass air flow. The instrument we plan to manufacture ourselves is a venturi meter for the air flow rate that will be placed on the air cleaner, and another venturi for the volumetric flow rate on the cooler. Also, to measure relative humidity we plan to use a sling psychrometer. Next week we plan to meet and begin working on the poster board that needs to be ready for Winter design review while starting to order and manufacture the parts we need for the engine. We will also begin hypothetical combustion calculations.

By Daniella Lopez, Engine Test Bed