350 TBI first time rebuilding engine...question
Looked on Summit Racing at the head gaskets for a 93 350. The compressed thickness is .041. This would give you a Static Compression Ratio of 10.562 and a DYNAMIC EFFECTIVE COMPRESSION RATIO of 8.790 which cannot run on 93 octane gas with a set of iron heads without detenation. You have a TBI system which is computer controlled. I can see the computer trying to reduce the timing because of the knock sensors. Getting somewhere around 6 miles to the gallon of gas because the timing is retarded so much. I would try and clean the pistons up with some degreaser (Simple Green). Mix some Simple Green with hot water to clean them and dry them immediately to prevent spotting or turning white. If not maybe you can sell them later. But you definetely need the 9902HC pistons if you want to use this motor for the street. Maybe someone else can come along and give you some better advice. Good luck.