If you are a tuner you might, maybe, pick up 10 hp...........stock camshaft for a 190hp 273 is not going to pull a lot of air; at this point in it's; the engine; life, the springs are kinda soft, so it will pull even less..........not to be a downer, just a realist, a 4 bbl intake, carburetor, and headers do not guarantee lots of HP, just the possibility.....to get everything out of what you have, you need more camshaft and compression.
