No its not, thats way too big for a pilot jet. It may be different for every motor. However, I ride with four ported 350's, Two 4 mill strokers, and a 7mill stroker that all have 2 into 1 carb setups. Out of all those 4 of them have a 35mm pwk. Out of the four with the pwk, none have a pilot jet over a 50. That is so much gas, that if you need a pilot bigger than that, then you have an air leak or something. A 58 pilot is ridiculously big. No one on here that knows how to jet a 2 into 1 without asking for help runs a pilot jet that big. Do a search, I just pulled up a ton of 2 into 1 threads, and sredish never once said to try a pilot jet over a size 50.