Holley 1945 Rebuild

No, a larger jet will only make more power if the engine is lean to begin with. If it's about right, you'll just use more gas. If it already has a 62 in there, you can probably leave it. If it is smaller than a 62, you may want to consider putting a 62 or a 63 in there, but that's just my experience. What is in there now?