So I've got a 390 in my 55 f100. Recently had heads gone through, did a Crower cam and lifter kit, double roller timing set and a holly street warrior 4bbl. After about an hour of driving I noticed what sorta sounded like a failed lifter, however the noise goes away under acceleration, and when letting off the throttle and at idle. But when cruising I get a noise that sounds like a collapsed lifter. Y'all got any thoughts? I did notice that it seems to be running quite rich, and it's not pinging either. Any input is greatly appreciated!

 

Sounds sorta like an exhaust leak? It starts out ticking under load and backs off as it levels off...

 

No it's not an exhaust leak. It's while cruising, not under acceleration, not when coasting or at an idle. So under acceleration you can't hear it, doesn't get louder with more throttle, it's noticeable while cruising; steady throttle, under load. Doesn't do it free reving.

 

Stuff like that reminds me of a wrist-pin noise.

But you usually hear that sorta "blip" for a split-second when you free-rev and pop off the throttle.

 

Darn I sure hope it's not a wrist pin.

 

I've also got some oil blowing out both valve cover breathers. I'm debating on pulling the motor and going through the bottom end. Before the head job and cam swap, it didn't blow any oil out of them.