Long story short, big argument with my dad not letting me add any 'upgrades' to my Chevelle to make it a bit faster due to it being original matching #'s...(won't even let me put a 4-barrell carb on! :rolleyes: ) After him finally having to ride in it last night, he admitted it wasn't nearly as powerful as it should be (it's no big block, but even a 2-bbl 350 should be more powerful than mine is). He thinks he hears a lifter rattling inside and that I'm maybe not running on all cylinders because one cylinder's valves aren't opening. That could possibly explain what we agree is a huge lack of performance. He thinks it could be just an exhaust leak, though. If we find out it isn't an exhaust leak, is there a way to tell if valves aren't opening without pulling anything--or are we looking at a valve cover/maybe intake manifold pulling to check and reset valves, etc.

Since I am the main driver of the car though, I've never really noticed it until he pointed it out. Either I've missed it before or it's new. New makes me think it may be exhaust leak, though. Is it possible there's been a bad lifter/valve lash and it's just now making noise though?

Thank you.

Is the valvetrain all original? You could have a stuck lifter or something of that sort. I have a friend with an original 307 that is ticking like mad right now, and its not an exhaust leak. It still runs though but he has a 383 sitting in the garage that is almost done.

First things first i would do a valve adjustment to make sure you are taken care of in that department. Since it is a hydraulic cam motor it is pretty easy (although slightly messy) to do. Once you do that see if they are still making noise.

Daniel