No i didnt really get a good luck at the lobe on cylinder #4. I went ahead and prepped the heads today for removal tomorrow Ill only have the head bolts and alternator bracket to remove. I will pull the heads tomorrow and get them to a local machine shop. Rods looked good will be replacing them even still but still wonder why #4 rocker was loose? should I just replace all rocker arms as well? I will most likely.
Im going to go ahead and start the AFM DOD delete process. Ill be using a stock cam and will have my ecm tuned by Brendan @
http://www.lt1swap.com/afm_delete.htm
Kit:
https://sdparts.com/i-24048327-sdpc-dod-afm-delete-kit-for-5-3l-ls-engines.html
Cam:
https://www.summitracing.com/parts/...g0su0K0m9UqW_lcgpxt29usvPBbUcxvxoCQqkQAvD_BwE
Second verification of these parts is greatly welcomed.
*wish i could go more performance on the CAM but no local tune shop
Sprocket? will I be using my stock sprocket or would that need to be replaced for the new cam?
Given your other symptoms, I'm banking on that rocker being loose due to a collapsed AFM lifter. You could do more troubleshooting to come to a diagnosis, but none of it matters if you're going straight for the AFM delete.
I'm a fan of having AFM tuned out by that guy cuz it's super cheap. It's only a fraction of what a Range costs and you don't have the issues a Range can cause.
SDPC doesn't specify what brand the lifters in that kit are. I see they offer Delphi lifters for an additional $159.80. I would STRONGLY suggest getting genuine Delphi lifters. Yes, their price (and most all GM parts) has skyrocketed since the GM strike and then COVID. But, they're worth it to not have to go back into the engine (new head bolts and gasket(s) to replace a failed cheap knock-off lifter while hoping it didn't wipe out a cam lobe.
That cam is slightly smaller than the original. It'll work and be fine and you'd probably not notice any loss of power. I wouldn't let it hold up the project, but I'd look for an L33 cam, new or good used condition. The L33 cam specs are identical to the stock LMG specs, just without the AFM lobes. On the other hand, since the heads are going to a machine shop, they should be resurfaced as standard procedure. They shouldn't have to take any more than around .003" to .006" to get a flat surface and appropriate RA. But, since they're already being milled, you can have them deliberately shave off something safe like .010" to slightly bump up the compression. This would make up for any loss the smaller cam might bring. Unlike a cam, it would add power across the entire rev range. To be on the safe side, I'd run 91-93 exclusively. Really, these things need 89 at a minimum even in 100% stock form. Running high octane would cost a few bucks more per tankful, but you'll get used to it. The better MPG would offset some of that cost and you'll appreciate the extra power. If you do get an L33 cam, you'll need the 3-bolt cam sprocket that has the 4X reluctor that the GenIV engine runs on. This is GM #12586481. You'll also need the three cam sprocket bolts, GM #12556127 (you'll need 3). I always use ARP for the cam sprocket bolts: #134-1003. If you go with that Summit cam, you can reuse your stock cam sprocket, but get a new bolt.
The stock rockers are fine. At 147K maintained miles and with keeping it a stock build, they have lots of life left in them. With the cost of GM original parts the way it is right now, replacing them would be a splurge, IMO. I'd run 'em if they all checked out fine.
On this build, stock push rods are fine. Roll 'em on a piece of glass to ensure none are bent. Inspect the tips for any roughness, indicating a lack of oiling. If they're all smooth and shiny, reuse them.
I have a decent amount of pics and details in my build thread if that would help any, at least with ideas and/or foresight. I started out with a stock AFM delete in mind, but a buddy messed that up for me. I ain't even mad, tho. lol
