If the issue was a gradual one, the car would have started to act up before the failure. The timing would be off and drivability would change. There would have been indicators to tell you something was not right.

I've been working on cars for 15 years, and I've seen some really bad valve to piston contacts, and none of them have thrown a rocker. Even on high rpm timing belt breaks.

This reminds me of SR20's that have seen high RPM abuse in drifting. The problem is caused by overreving the engine and the rocker arm gets thrown off. The loose rocker can create all sorts of carnage.

Looks like the rocker lodged itself against the cam and head causing an immediate stop and the resulting damage ensued.

 

Is this the car that DB posted on Facebook openly slagging Kelford for? If it turns out that it isn't a Kelford fault, it's probably worth clarifying.

 

This happened after 40 miles of driving on my part. The car arrived here in NJ from Ca. the day this happened.

DB and the previous owner both said it looked like high RPM damage, since I had the car it NEVER revved over 7k rpms....and I didn't miss any shifts. When it stopped running it just shut off at 3k rpms. It just shut off, it didn't over rev or anything like that, in fact there were no odd noises at all....well until just before we came to a stop. The engine was off a that point and we were coasting, with the clutch all the way down.

The only indicator to me was that it anything was wrong was in 3 or 4 gear at lower rpms, if you stomped on it it would hesitate really bad. I thought it was the tune and did it 2 times, the first and then I tried to replicate it once to see if it was consisitent. I thought it had to do with the tune so I figured I would just get it retuned as quick as I could and I made a point not to do it again.
Since I only had the car for 40 miles I didn't know if there were any changes in the car's behavior.

 

I have no clue, I don't follow Facebook.

Was it recently?

EDIT---I went on my wife's account and looked. This is not the one. Look at the pictures. The one he was bashing them for was a cam that snapped. He didn't blame Kelford for my problems as he didn't tear down my motor but after looking at these pictures his response was "I do not run, sell or recommen Kelford cams. I've seen and heard of similar failures and seen some bad stuff on some other brands too."

In the end all I can say is that I am glad I listened to him about these cams and decided to go with GSC-R2 cams. If I didn't I would have probably put he motor back together with the Kelfords and had no inclination of what went wrong and then I would have been in the same boat I am in now in another 5 miles.

Guess I owe DB a big thanks!

 

I'm not pointing fingers, just stating what my experience tells me.

 

No. That picture the cam itself actually snapped.

 

Yeah as both DB and previous owner did.

I am not implying anything, just telling people what actually happened. I have no reason to say anything other than what actually happened because it has no bearing on anything. What happened is done with and now I am paying for it regardless of how it happened.

After I found this damage to the cam and cam gear it was evident to me that this is where the problem started based on the events. Which is why I made this thread looking to see if other people agreed.
All of the intake side rockers were spit off but the exhaust were all on.

 

Also, I don't think your theory explains how that happened to the cam. I can't see that happening from one event.




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If all the intake side rockers were spit off, they can easily lodge up against the cam and side of the head not allowing the cam to rotate, coupled with the timing belt pulling on the cam sprocket, the force could have caused the dowel pin to break out of the cam as it showed in your first pic.

We know it was not a gradual issue, pretty much instantaneous. And the experience mechanics here will confirm with what I said earlier. Valve to piston contact does not cause rockers to jump off.

Try not to see this in an argumentative way, this thread just got my curiosity piqued.

 

The damage to the cam gear was collateral from the valve train abruptly coming to a complete stop not the cause or start. It looks to have happened in one event.
The damage starts at the dowel pin alignment hole and drags through one of the elongated oil holes which are located at 3 and 9 o'clock on the back of the mivec gear it also even seems to have damaged the opposite elongated oil hole to a small degree as well. the whole sweep on the back of the cam gear was scored in the opposite direction of rotation which says the intake camshaft stopped and the rest of the valvetrain including the mivec gear kept going.
It was not shifting back and forth like some seem to think. The camshafts dowel pin hole also does not exibit damage that is in line with back and forth shifting, it only shows damage caused by a single shearing event in a single direction of load.

Here's a pic of an undamaged mounting surface for reference.

 

I agree, the damage to the back of the cam gear was caused by an abrupt stop. What I don't agree with is how the cam was damaged like that. I just don't think the cam damage could be caused from one event. I think that the damage started there.

I am not trying to be argumentative, just trying to debate what went wrong.


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Well that's fine, I'm not trying to convince you otherwise.
I'm just saying from my experience I can see exactly what the chain of events were, now what caused that chain specificaly to start is another story...
You also seem to keep grossly underestimating the forces at play here, the damage to the camshaft and gear could be easily and in my estimation definitely cause by a single shear event. But even if that cam gear catastrophically failed and flew off it still wouldnt have spit the rockers out and destroyed the head like that. Your faliure started with the lifters and or rockers more than likely... not the cam gear, that was collateral imho.

 

besides with the rotational speeds and force loads the timing components see, an intake cam gear that was shifting back and forth would not be a trivial thing. You would have known right off the bat as soon as you fired the car up if it fired up at all. Not to mention the mivec position error codes it would have thrown. My vote goes for collateral damage, original faliure was somewhere in the valvetrain most likely.

 

I still don't agree with that theory about the cam dowel hole from this event, from my experience with metals I just don't se it happenening from a 1 time force.....well atleast steel on steel. I understand that the physics here show lots of energy coming to a stop at once but from my experience with steel I just don't think it is possible unless it was moving over time.
If the chain of events were as you are theorizing don't you think the cam lobe would have been all torn up? Either way I am surprised the cam isn't scored badly, there is no doubt that a rocker was wedged between the cam and the head cracking the head.

If the timing went off by a decent amount, whether caused by the cam issue or something else, wouldn't this damage to the rockers be possible?

I ordered new lifters to be on the safe side.....don't really have the extra $$$$ but I can't take a chance. I had GSC no tick lifters but I just went with new OEM lifters. I have heard of a few bad GSC no tick lifters so......The intake side rockers were already swapped out, just decided to do the lifters for added piece of mind.

Most of the rockers that were spit off also had broken tips, the part that sits on the lifter was broken off. The cams were still timed together, well atleast the timing marks lined up but the crank was like 90 degrees out when the cams were lined up with the valve cover marks.


Here is where the mask on the exhaust cam was when the crank was at TDC


First look after removing the valve cover

 

It would not be possible for the intake cam gear to mechanically shift around between 0 and 180° off and have the engine run with any kind of reliability or at all for that matter, thats not even factoring in the mivec trying to change the timing position. And again the camshaft dowel hole is only damaged in one direction, there are both acceleration and deceleration forces put on the cam gears so if it was shifting back and forth while running there would have been damage in both directions in the camshaft dowel hole and driveability problems at all rpms.

The damage I see just doesn't seem to add up to your theory. These kinds of faliures are interesting, chicken or the egg....