That damn Busch lite

You thinking of rebuilding or mobbing?

 

Calling that noise piston slap isn't going to help hold your motor together.

 

Rebuilding. Going to hopefully get it in next month. Going to cost as much or less than a used engine, and I won't have to worry about cast pistons or ring clearance.

 

That's what it sounds like to me- identical to how it sounded when cold. I've only had a gen1 sbc that ever had rod knock and it sounded much louder and deeper. What do you think it sounds like?

Oil pressure hasn't changed. I'm babying it and staying out of boost until I get it in.

 

Quick update. Did some diagnostics on it.

The tempo seemed slower than I would expect for rods at 625 rpm idle. I tapped out the knock with an app to get beats per minute and it came to 300-310.

Only had time to pull 1 valve cover tonight on the side I don't think it's coming from (passenger) but it looked ok. I'll be doing rockers in the future but nothing glaringly bad.

With the engine running pulled 1 plug wire at a time. No excessive blowby that I'd expect to see from a bad cylinder in the intake tube. No change in the sound so I'm leaning towards lifters. When I bought the truck this was mentioned as probably needed by the seller but the fact it went away hot lead me to believe it was piston slap. That leads me to oil.

​​​​​​OIl pressure is still normal for this truck. Hot is 25 at idle, and 35-40 psi at about 2k/75-80ish on the highway. I added .5-.75 a quart to see if it helped with pressure and it did remain higher as well as build more pressure and faster so guessing my oil pump and I ring need done, too, and probably was not doing me any favors at 6k rpm.

 

This won’t help your current situation with the knocking or what not but do you have the updated valve cover and LS6 valley cover? Just curious as your oil pressure seems low as ***** but maybe I’m out of my element here

 

No idea. I'd have to do some studying up on that topic. Mine is whatever came stock on a L9H. No afm but I have vvt.

 

Gen4 can't run the LS6 valley cover, don't worry about that

 

I think it sounds like a lifter turned sideways. Maybe the sound you heard since the beginning was a bad lifter, and then when you whiskey revved it, the lifter turned sideways. A piston slap has no "tink" in its sound, it's a deep inside the engine, quieter than a rod knock, but sounds like a small-end rod knock.

 

??? What gives you that idea?