So I don't get on the forums much anymore, especially since sadly everything has been taken over and is now controlled by Facebook and Google. But I recently heard a noise so I decided to pull the motor and tear it down.
So I heard what I was hoping was a belt tensioner but after further inspection with a stethoscope, I confirmed it was the classic cam lobe chirp noise. Before I pulled the motor and tore it down, I could tell with the stethoscope it was somewhere around the #4 cylinder. So I got the engine pulled and pulled the passenger side head (I couldn't pull the drivers because I don't have a 13mm hex head socket and didn't want to risk using my 14mm hex head socket for the driver's special head bolt). #4 definitely is the worst, and by a good bit compared to the others although all of them still didn't look great but more ok.
So I have only had this Cam Motion cam in for less than 15k miles. Its a 226/238-114-.630/620 (XA226/350-XA238/345-14+3) and I believe it is on a stock/OEM 5150 core. Before I had a TSP with basically the same specs and both have been running on PAC .660 dual springs. I have been through 3 different size pushrods lengths hoping that I could get it more quiet but I was within the recommended preload. I switched from the TSP to Cam Motion cam after my stock valve seats got destroyed. So I kept the same PAC .660 dual springs and Johnson lifters and switched to the Cam Motion cam.
The oil had also been loading up with metals as well. Thankfully the rest of the engine appears to be fine. The valvetrain, rocker arms, pushrods, springs all seem ok. I did have a very small piece on the very bottom of my PAC springs break when I had the TSP cam.
So at this point I really think I want to just go back to stock. If I could find it, I would get the GMPP cam and not worry about it anymore but you can't find it along with the converter they used to have for the 8L90.
I was looking at Katech stuff as well. I know BTR is making a lot of claims about Spintrons and valve bounce, which I am glad they are talking about it at least but not sure if they have really done the testing and development for a stable valvetrain.
If I decide not to go back to stock and get another cam, I am going to flycut for more clearance so this at least gives me an opportunity to do that. I just wish it didn't cost so much to tear these things down. You can easily spend almost $500 in gaskets, bolts, and hardware if you want to take the heads off and open it up and rebuild it "right". I am using a Cometic 0.028 gasket to get my compression as high as possible and they alone are almost $250 which I know reusing them is a controversial subject and I almost think it could work, but with the work it takes to pull the engine it probably is worth the extra money to buy new ones. I think after you have torqued it and ran it up to temp and cycle it, the rubber/viton overmold comes off and I would be worried about the seal after that.