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Discussion Starter #1
I now have ~7000 miles on my car since DOD-delete and such, and about a 1.5 weeks ago, I started getting a less-than-nice noise from my engine. Sounded lifter-ish, or other related ticking. Continued getting a bit worse, and was more noticeable once the oil was hot.

Jump to 2 nights ago, I'm replacing my spark plugs (different story), and while I'm there I decide to pop the valve covers off to start investigating said noise. Driver's side is perfect. Nice and clean, rockers all in place, springs look good. Go to passenger side. Looks about the same, but then... see attached pics... one of my trunnion snap rings is in many pieces. Ended up finding one more piece like the 2 in the pic, but it's only enough to account for about 1/6th of a snap ring.

So yeah, going to pull the engine out of the car in the next week or so, and figure out where the rest of that snap ring wound up. More to come.
 

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Engine is out. Found some more snap ring in the oil pan (see attached pic). So found about 3/4 of the snap ring. My best guess on the failure is that the bearing wasn't quite pressed into the rocker all the way, and therefore caused the snap ring to rub on the trunnion and weaken it. You can see a small groove on the inner edge of the bigger piece of snap ring. And that bearing is slightly proud of the rocker body. Oh well...

Engine is headed to the machine shop on Friday for a bottom end rebuild. Still not 100% sure what was going on, but I contemplated a full rebuild when I did my DOD-delete. Either way, it will all be fresh and some parts changed/upgraded. Going to switch from Delphi LS7 lifters to Johnson 2110's. Also changing the cam, water pump, and balancer to parts that are made for a certain belt driven intake manifold. :)
 

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Way to make some lemonade from your lemons. I'm contemplating changing my cam also, but sure is a slippery slope..
I hope so. Could be rotten lemons. haha

Why the change?
 

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Probably a good time while it's all out.
LSA was my goal when I did the DOD-delete, which is why I went with the ZL1 converter, and a few other things. However, I ended up getting away from that goal as things progressed. Now it's real. haha

Talked to the machine shop this morning. He convinced me to get a set of forged pistons. May get rods too. Any recommendation from anyone? Currently looking at Wiseco flat tops and K1 rods. Didn't really plan to build an engine this month, so bang-for-buck is a big consideration.
 

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I hope so. Could be rotten lemons. haha

Why the change?
I currently run the LPE GT9 cam. It's pretty rough on the valve train. Plus it isn't really optimised for twin turbos. I'd like to have something speced for my combo, taking into account a converter I would do at the same time.

For rods, I beam > H beam.
 

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Gotcha. Makes sense. I knew you had talked about doing a converter. Might as well do the cam too, and get that 9. Although, I'm guessing a converter would get you there.

Noted on the rods. Thanks
 

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Crap...what trunnion kit were you using? Greg mentioned that I should pull my valve covers and check mine since I've been having a little extra valvetrain noise. My noise hasn't gotten any worse in the month or so that I've been hearing it and I drive my car almost daily.
 

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Discussion Starter #10 (Edited)
Crap...what trunnion kit were you using? Greg mentioned that I should pull my valve covers and check mine since I've been having a little extra valvetrain noise. My noise hasn't gotten any worse in the month or so that I've been hearing it and I drive my car almost daily.
BTR v1 kit. As I've investigated more, it does look like install error, with the bearing not seating in the rocker far enough. So can't blame the product. My machinist is really curious about it too, he asked me to bring it in for him to "do an autopsy". So we'll see what he has to say as well. Hoping I can just replace the one, and roll with the rest. I'm just glad I found it before it decided to blow the bearing out, there was nothing to stop it.

Edit/Note: The rocker bolts were all still perfectly torqued down, so that's a win for that kit and bolt design. I was somewhat expecting a loose rocker.

I always had more noise than I thought it should, and particularly in the last couple weeks before pulling it apart. Some of it was exhaust leaks, but the latest noise was right after having the exhaust fixed, so who knows. My fear is... I did an oil change which may have moved some of the chunks around in the oil pan. It wasn't long after that, that I started getting more noise.

I ordered new cam and Johnson 2110 lifters last night. Machine shop is going to do the pushrod/lifter preload measuring, so I'm confident any noises will be appropriate noises. lol
 

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What machine shop are you using?
Rockville Ring and Bearing. Doug, the owner, is a great guy and builds some incredible stuff.
 

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I currently run the LPE GT9 cam. It's pretty rough on the valve train. Plus it isn't really optimised for twin turbos.

I love the GT9 in a PDS setup. Its got a nasty ramp rate, but I have never personally seen any valvetrain failure with it. You can easily make 800+ rwhp using this cam.
 

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I love the GT9 in a PDS setup. Its got a nasty ramp rate, but I have never personally seen any valvetrain failure with it. You can easily make 800+ rwhp using this cam.
I'm already there. Still, if I could get something specifically for my combo that would also be easier on the valve train (and hopefully less noisy) it would be a win all around.
 

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UPDATE...

Machine shop has been rather backed up, so finally getting around to the point that everything is torn down and about to order the new parts.

Didn't find anything to alarming inside the engine. No signs of that snap ring tearing stuff up. Machinist is guessing the noise I was hearing was likely a lifter, which was my guess at first as well. Must have caught it early though, as it didn't damage anything yet. He did recommend going .005" over on the bores to give a fresh start. He said, "cylinder walls look good, but could be better."

I'm about to place an order for new parts, anyone have any suggestions outside of the list below?

- Wiseco K398X05 - 4.005" pistons (rings will be gapped for boost)
- K1 012AE25613 - 6.125" rods (pistons are made for the longer-than-stock rods)
- Wisceo S718 - upgraded wrist pins (do I need these???)
- ARP main studs
- ARP head studs
- LS9 head gaskets

I already have the following:
- BLP Keep Hatin' LSA cam
- ATI LSA damper, which will be pinned by the machine shop
- Johnson 2110 lifters
- Pushrods will be measured for and ordered
- Shop will provide all bearings

Anything I'm missing?

Also, ready to have my car back...
 

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Sorry seeing this post a lil too late. I went with Mahle Forged 4032 pistons gapped for forced induction per their specs. Mahle said the pistons would be good for 15#'s of boost. Just buttoned my motor up last night on the stand. I installed the BTR trunnion kit.
Which kit failed on yours??
 

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Discussion Starter #18
UPDATE...

Machine shop called yesterday: 7 pistons are identical; 1 of them is 0.0015" too small. He had already contacted Wiseco to see if he should just match one cylinder to that piston. Wiseco said, no, they'll send another matching piston. Cool.

Anyone in the DC area, Rockville Ring and Bearing is awesome. Nothing but great service and very high standards.

Hopefully down to 1-2 weeks then I'll get my car running again.
 
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