The B-29 was originally fitted with the Wright R-3350-57AM engine, which had a less-than-desirable reputation since its inception. True to this reputation, FIFI has experienced numerous problems with her engines in the 30-plus years she has been flying with the CAF. Following the discovery of metal shavings in the engine oil, the B-29/B-24 Squadron held a lengthy series of meetings with CAF personnel and experts in the field of aircraft restoration, and the decision was made to not fly the plane again until it could be fitted with engines that are a custom built combination of the R-3350-95W and R-3350-26WD engines. The refit required reworking the engine mounts and some of the engine cowling, making it a lengthy undertaking.
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