Valve train questions/issues

Well, I can't really argue with that now can I?

That definitely seems to be an issue with high(er) valve lift and inadequate valve head recession relative to deck. Sorry to learn about your misfortune. That really sucks. It's not called the school of hard knocks for nothing.

laserjock's problem looks more like valve float though, as it occurs at higher (3000 ) rpm.
It could be that piston to valve clearance is running at the ragged edge, but the higher rpm pushes it over the edge.

I'm just thinking out loud. The input of you and others that have "been there, done that" is so valuable. I, for one, really appreciate that you can share your misfortune so that others may benefit from your experience.

I suppose we'll just have to wait for the autopsy. I'd really like to know what the valve spring pressure #s are on Mike's engine and what the recommendations are for the TYP4 cam. @typ4

Other than the valves leaving little "reliefs" in my pistons I had no damage to rockers, valves or pushrods.
So...as I explained, I had solid contact piston to valve just turning the motor over by hand leaving little damage.
I have to assume the lifters absorbed the hits.
Now think of the carnage the OP experienced that your thinking is valve float.
I'm far from being an expert but I don't think so, and, no you cannot hear the pistons kissing the valves, it just sounds like the rattle we're accustomed to.

Milled heads
Deep recess of valves
Either shim out rockers as mentioned maintaining pushrod length at current state and rocker contact as is seen
Or run shorter pushrods and run rockers w contact as is...and seen....

Neither is ideal.

There is one hella lot more to valve train geometry than whats going on in this thread....

As for milling pistons..you can get cutters to machine slightly larger than valves and creat small recessions..thus negationg full face loss of piston crown....it would be my preferred way..

At this point I myself am going to stat watchingfor turbo pistons in 010 or 020 over for my fully sleeved engine build

Russ told me that someone used his cam and retarded the timing one tooth. It's working fine. It seems like someone (Macrobb perhaps) said that you're supposed to do that with Justin's cam. Maybe that's the secret?

Its not the way it was originally designed. When I get to the bottom of this I will be posting a fully informatve write up.
I did not grind the cam, Delta has screwed up the cam and will not take any responsibility for it. Im done with them.
Most cams have been trouble free, some obviously have not. And its random so I cant have that in a camshaft . Some of the lift varies by as much as .030 with an indicator zeroed on the base of every lobe.
So did I find the problem? Yes. Can I blanket fix it,no. I wish I could tell everyone to toss them and id replace them, but they will only give me another cam, anyone want to roll those dice? Not me.

30 years of business down the drain.

I am very sorry for the troubles, I will do what I can.
Im working with Oregon cam grinders for a drop in, their grind is so close to my original from delta its scary, that said, it just reinforces there is only so much you can do in a stock parameter engine.

Also, if I cant get a drop in camshaft available that works as good as mine I will stop selling them.

Hydraulic lifters are designed to have nearly .250 of useable travel and will perform correctly in that range.
I read that in Engine Builder magazine a few years back.

Also ,one of our members near me has the first Oregon grind and is going to Check it out in his new 6.9 build.
And when I dial indicated it the lobes were all within .004. That I can live with since my brand new IH cam is .003

Thank you for the info typ4. Can't wait to see the results with the new cam

laserjock said:

Did some reading this morning. Sounds exactly like valve float on a hydraulic lifter as described by a guy on HAMB.

Miss for a few seconds until the hydraulic lifters bleed down then normal. The bang I heard was probably piston valve *********** as the lifter bled down. Probably have another bent pushrod at a minimum.

Sigh. Guess I need to suck it up and do this.

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Looks like you're on its tail... But since you're asking what we would do, if I were in your shoes I would honestly take it slow. Think through every move quite a bit before striking. First, keep it well under 3k!! Pull valve covers, check EVERYTHING you can. Contact the company with results. And post here. Honestly I'm not too savvy on the internals side of things, I'm more knowledgable about the outside of these trucks (body work, axles, fabrication) but that's just my .02. I just know theirs nothing worse than trying to solve an issue and in the process causing another... I'm going through that right now.

Thatoneguy said:

Looks like you're on its tail... But since you're asking what we would do, if I were in your shoes I would honestly take it slow. Think through every move quite a bit before striking. First, keep it well under 3k!! Pull valve covers, check EVERYTHING you can. Contact the company with results. And post here. Honestly I'm not too savvy on the internals side of things, I'm more knowledgable about the outside of these trucks (body work, axles, fabrication) but that's just my .02. I just know theirs nothing worse than trying to solve an issue and in the process causing another... I'm going through that right now.

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Your a little behind.

laserjock said:

Your a little behind.

You must be registered for see images attach

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You're just workin that fast

@typ4 thanks for the updates Russ.

laserjock said:

Your a little behind.

You must be registered for see images attach

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Dang it! Lol sorry about that. For some reason sometimes my tablet doesn't show multiple pages. I thought I was commenting on the first page :')

No worries man.

How did you end up resolving the issue?

Well, I pulled the motor and sent it back to promar along with a new factory stock cam. On teardown, they found piston to valve contact on the intake valves. They put it all back to stock and so far so good other than the oil nightmare I had. That’s not related. Russ will tell you these engines are real close. I know they didn’t check it for clearance with the torque cam but it is what it is for now. I still have the torque cam and when I get around to doing one myself where I can check and re-check everything, I’ll probably run it. I can tell you the truck felt stouter with it. But bending valves and pushrods is a bad thing.