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The CMS experiment uses a multi level triggering system to filter the most interesting and useful events for permanent storage. When reconstructing electrons for the high level trigger (HLT) system it is vital to keep a very high signal efficiency when matching up the inner tracking system hits and the electromagnetic calorimeter (ECAL) showers, while at the same time keeping the background rate low. This is achieved by matching pixel hits in the inner tracking system to superclusters in the ECAL. This pixel matching was last optimised in 2010, but for Run II we will face higher pileup, more particles per interaction, and smaller bunch spacing, so we will need a new, reoptimised pixel matching algorithm. I will present my work on the topic using a novel technique and new variables to keep the HLT rates under control.