I am having trouble with my stock rockers.

To give you a little information about what I have:
This is an '04 5.7L punched out to a 392.
It has Thitek heads with 2.165 intake, 1.65 exhaust, dual springs; PSI 1512s.
Comp Cam with gross valve lift, intake: .636, exhaust: .620.
Comp Cam hydraulic lifters: 15820-16.

Everything has about 50 1/4-mile passes on it, except the stock rockers. I did not see a problem with them, so I ran them.

My problem is, after inspecting the rockers and valve stems I noticed that some of the intake valves only (1 intake valve on the right bank, and 3 intake valves on the left bank) were mushrooming at the top and obviously the rockers were showing damage as well. The exhaust valves were unaffected. I do not see any bluing or other signs of oil starvation. According to my engine builder, the pushrod lengths were checked with zero lash, plus 20k. After talking to Comp Cams, that is correct for this particular lifter. The pushrod lengths were 6.920 and 8.240.

I have not removed the heads yet to replace the intake valves, so any thoughts you may have would be appreciated. I have also considered installing lash caps, what are your thoughts on adding those?

Thanks,

PS This is the same combo as Triple Threat except the heads.

I just measured stock pushrods at 6.80 and 8.08

Ken, send me a message when you get up. There is something else I want to bring up with you

Update on the rocker situation:

After extensive research and discussions with a few people on this forum, I came to the conclusion that the intake valves were borderline too heavy for the PSI 1512 springs that my Thitek heads came with. I replaced them with PSI 1513s, but I didn't stop there. I have replaced all of the rockers, intake and exhaust, with brand new sets; replaced all of the intake valves and machined the valve stems down to compensate for lash caps I added in the hopes that I can eliminate the rocker wear that seems to be fairly common with these engines.

I have to say I like the looks of the lash caps and how the rocker pads fit on them, the valve stems are 8mm, the lash caps are 11mm wide and the rocker pads are 10mm. So it seems to give a much more stable contact point. I also shimmed the rockers to make sure the pads were dead center on the lash caps.

Reassembled everything; I now have around 45 runs, and with each inspection everything has been looking good so far. At this point, I have to come to the conclusion that the valve springs being too light for the valves was the main culprit. However, the size of cam I am using may have just brought this to light a lot sooner.

I hope this information helps others in the future so they don't have to go through what I have been going through with this. Thanks to everyone who came up with suggestions.

Define border line too heavy......And where were the rockers being worn/damaged?

Yes, the theory is that the intake valves, which were the only ones affected, I was told weigh about 125 grams. If you go to the PSI website and look up the 1512 springs, they are fairly light. The rocker contact pads were wearing off, but the biggest issue was that the valve stems themselves were being worn down, and the worst one of the 4 measured out at .080 worn off after 50 runs.

Curious what RPM were you turning the engine? Have similar issues with my deal but a solid stem 2.18 valve and a beehive manley spring. My issue is I will need to change all the valves to get a dual spring on it. Thinking about a PSI 1516 spring and 2.18 hollow stem valves. Turning my deal 7500 but it is not happy at all in the valve train department.

Shift at 7K and go through the traps at 7200. I have the solid stem valves. Had I known what I was getting into, I would probably would have ordered the heads with the hollow stemmed valves. For now everything that I've done seems to be working. A lot of people I have talked to seem to like the idea of the lash caps, but of course, only time will tell.

How much material did you machine off the valve tips? I was considering the same thing but the tips are short to begin with. I am thinking of using 6.1 valves in Eagle heads because they are .100" shorter so with .080" thick lash caps the geometry would end up close to stock. It will shorten the installed height of the valve spring but there is room to play with there.

.080 but with my setup, the valve length wasn't even a concern as I had plenty of room. Again, these are Thitek heads and my springs are dual PSI 1513s. I had plenty of clearance between the retainer and rocker during the full range of motion. As I also mentioned previously, I shimmed the rockers to center them on the lash caps. Since I was not able to find shims for the rocker shafts, I went back to the old rocker shaft shims for the small block Mopars. They were very close, and with a little modification fit the Thitek heads.

Great info here! Craig set me up with hollow stem intakes and the 1513 dual springs in my Thitek heads so hopefully I wont have this issue.

What size cam are you running?