LS7 Rocker Arm Help
 

Hey all,
I'll preface with the fact I'm as ignorant as I can be when it comes to anything that isn't bolt-on or a fluid change.

That said, having an issue with my solid roller LS7. Been having a fairly loud valvetrain tick recently. Barely noticeable outside the car and at idle, but very noticeable inside the car and above 1500rpm. I've narrowed it down to valvetrain by running without the belt, and pulling each coil wire one at a time while running to locate any knock. I know it isn't driveline related, since it follows RPM and not wheel speed. I'm having the hardest time finding it with a stethoscope as well. I've checked all the pushrods, they all roll flat. No bearing issues on the stock rockers. I've checked the valve lash (since solid roller). Pulled the lifters (valley cover is milled to be able to change lifters w/out pulling heads) . They look fine. Can't see any uneven wear on the cam.

Only thing I'm able to notice with my limited knowledge is that the stock rockers and the valves seem to be wearing unevenly. Cylinder 7 exhaust is the worst. There is a noticeable ridge on the valve and rocker. My thought is that the noise may be the ridges 'slapping' together when the valve opens.
I know I need to go with a roller rocker setup. The swipe area on the rocker is quite large with this cam (.675 lift).

I suppose my actual question is, should I go with a simple bolt-on roller rocker such as the Texas-Speed LS7 roller rockers, and shim it to set lash like I do currently? Or pony up for a set of adjustable rockers?

Current valvetrain specs follow:
-Cam Motion Low Lash Solid Roller Cam
-Morel Link-Bar Solid Lifters
-.700 Dual springs
-Chromoly Pushrods (8.100" / .08" wall)
-OEM Ported heads (Rocker stands milled off and pedestals cut to be able to shim each cylinder)
-GM LS7 Rockers

Thanks for any input in advance!

https://cimg3.ibsrv.net/gimg/ls1tech...75c7a1ba29.jpg
https://cimg7.ibsrv.net/gimg/ls1tech...618063bfd3.jpg
Cylinder 7 Exhaust - You can see the uneven wear and ridge on the valve.

You can do bolt on roller tips and shim accordingly. Put lash caps on your exhaust valves too not just your intake valves. That valve might need to be replaced.

Yeah the top of that valve doesn't look good. Since these are the OEM LS7 heads have you checked valve guide clearance to make sure your not dealing with worn guides as well? I'm still running the bushed stockers and call me lazy Darth but I still haven't installed the T&D's full rollers yet.

You lazy bastard.

Who am I to talk. I have a fuel pump I still haven't installed. Probably coming on 6 months now

The heads were reworked less than 3k miles ago. Neither the guides nor valves are OEM. I'm thinking that the stock rocker is leaving the center of the valve due to the lift. I went ahead and ordered some lash caps for the exhaust side as well like Darth recommended. May be able to smooth that #7 valve tip out a hair and put a cap on it.

Looking into a set of the TSP LS7 bolt on roller rockers to help minimize the side load. Anyone heard any horror stories regarding those rockers? My plan is to slap on those lash caps, bolt on the TSP rockers, remeasure for pushrods, shim to set lash, and send it. Tell me if that's a dumb idea or not.

Those T&Ds look really tempting. What did you drop on those if you don't mind me asking?

They generally can be had for about $1450.00

Cam Motion has them...... http://www.cammotion.com/rocker-arms...7-rocker-arms/

And Crower has steel shaft-mount rockers, BTW.

KW

Ouch. The Mrs. would kill me!
Think I'll stick to the TSP rockers and a pack of shims. It's a LLSR after all, so lash 'should' be set-and-forget.

Darth would know better than I but it sounds like a good plan though. The T&D's are between $1300-$1400 and nice pieces for sure. I figured if I ever decide to go LLSR these would fit the bill and still cheaper than going shaft mounted.

Well, I'll renew this thread with an update I suppose. Dang noise is still there!
I can't describe the sound. It's a fairly loud 'slap' that sounds like a metal marble going one revolution in a tin can very quickly. Follows and gets louder with RPM. Don't hear it at idle.
-I've drained the oil, looks as clean as the day I put it in there. Not one bit of metal or discoloration.
-New TSP roller rockers and pushrods are installed. Put lash caps on all valves. Was hoping these new parts fixed the noise.
-Lash took forever to set with shims, but finally got all valves where I want them (.008 - .010 hot).

Only thing I can think of is that I noticed my aftermarket intake manifold bolts are a bit long. On some valves, with the rockers off, the pushrod doesn't make the full 360* wiggle in the head without hitting the tip of an intake bolt.
I went ahead and cut about 1/8th of an inch off each intake bolt, and we'll see what that does.
Wanted to get any other possible input as to what could be causing this noise though before I throw it all back together. Any ideas?

Pic of new rockers for no reason.


https://cimg6.ibsrv.net/gimg/ls1tech...ffee27fca8.jpg

Nothing fell down in the engine when you put it together did it? Although, clean oil would say you don't have a shim or a bolt that fell down and merged with a piston.

Also, the T&D bolt on rockers are as expensive as the full T&D adjustables. Just get the adjustables.

The factory rocker LS7 arm I think the max lift they recommend is like .650-.660 due to the limits of the rocker tip. I think also they recommend not going above like 430 pounds of spring pressure on the stock rocker arms (per Brian Tooley website). Your new rocker arms look good not sure what that noise could be? Maybe an inner valve spring is broken so tough to see right away.

The motor was completely rebuilt about 1500 miles ago. Was running great on the stock rockers. Springs are rated for .700". This noise just popped up one day, no changes to the motor. Thats where the first post in this thread came in and I noticed the excessive wear on the stock rockers due to this cam. But the noise is still there after installing these new roller rockers. I was meticulous about making sure shims didn't fall into the motor this go-round too. Kept a count every time I installed and removed them when setting lash.

Tell you what, I'm never doing a solid roller again without adjustable rockers. Shimming took FOREVER to get just right :bang:

Yep, realized they were maxed out by the slight channels being worn into them. TSP said their roller rockers paired with my current .700 springs would work fine for this LLSR application. I glanced at each inner spring the other night, but didn't actually go over them with a fine tooth comb. The noise is non-existent on startup/idle and gets louder as the motor warms up and starts expanding.

That tells me it's a "lash noise". Some noise should be expected with ANY valvetrain that has lash in it, even if it's a "low lash solid roller".

My thought is to find a stethoscope and see if you can locate the rocker that might be making the most noise when warm. Then take that valve cover off as fast as you can and compare the lash of that rocker to another that you don't hear the noise on.

I'll definitely give that another shot in case the lash on one valve opened up more than it should have. However it's the same noise I had with the stock rockers that prompted the switch to these new roller rockers. Lash was the first thing I checked w/ the old rockers and they were all within spec. I still heard the noise too with the new rockers when I was in the process of shimming them. At one point, every valve had a slight preload even at operating temp. No lash at all and was still hearing it. The valvetrain noise for the first 1500 miles on this motor with good lash and stock rockers was very minimal. Sounded smooth and was actually quieter than the hydraulic setup of my old LS2.

Might bring it up to temp tonight, then run it w/out the valve covers and just pack some serious shop towels in there and try and pinpoint that damn noise :rotflmao:

This is a good idea. Shouldn't even be *that* messy.

Update w/Vids
 

Update: Took some videos to try and capture the noise. Don't know why I didn't do this before....
Rechecked hot lash tonight. All but two valves were within ideal range (.008 - .010). Only two had grown to about .013. Not a big deal, and definitely not causing this noise.

Videos located here: https://photos.app.goo.gl/9Uz69sR5UPYFDQGz6

Sure sounds like a spun bearing to me, but like I stated in an earlier post, oil was clean as day (thankfully).
Thoughts?

It's hard to tell what it is exactly but It sounds valve train related to me.

Update: Got the oil report back from Blackstone (below). Have been out of the country the last few weeks so hadn't got a chance to tear into it again. Guess I'll pull valve springs off and see if a inner spring is broken. If not, looks like the heads are coming off to check the valve guides. I can't imaging the new guides have worn that much in only ~1000 miles, but then again there was a LOT of sideload on them with this cam and OEM rockers...


https://cimg0.ibsrv.net/gimg/ls1tech...2c48e91cd5.jpg

Hey man,there seems to be excessive wear here,
I would recommend going to a lower viscosity oil.
20w 50 is too thick,
Use something like a 5w40 or 5w 50 at the most.