Ideas on wtf went wrong here?

I still think the bent stems are due to debris (loose rocker arm floating around) and the notch in the piston occurred when the follower had a chance to get on top of the valve spring and hold it open for a moment.
Literally nothing else makes sense.
The "why" the rocker arm came out is almost irrelevant, as it could be any number of reasons.
I would call this one an assembly error.

Wes06 said:

Even if the chain was off a tooth. How would it bend only the stems, not the face of the valve, and no visible ptv contact beyond that one intake valve.

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As the last poster commented, it's probably assembly error.

But the ptv was a intake valve and all the damaged valves are exhaust
@rocket

I still think the bent stems are due to debris (loose rocker arm floating around) and the notch in the piston occurred when the follower had a chance to get on top of the valve spring and hold it open for a moment

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The ptv contact and the follower that came lose happened on opposite heads. Are you saying the machine shop assembly is what cause this or how I assembled everything?

until you pull the valves and measure clearances your just speculating. Take it apart and figure it out, or take it to someone you trust. I wouldn't take it to the place that did the work.

Delete

Wes06 said:

But the ptv was a intake valve and all the damaged valves are exhaust
@rocket

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I've seen race engines pass parts from one cylinder to the next, its kind of crazy. I realize the rocker didn't travel from bank to bank, but I bet if you pull the engine and look inside the pan there is more debris.
How else can the be stem bent on top on the top side of the head? The valves don't mean the pistons on the same plane, so PTV issues would bend the valve head and leave witness marks on the piston every time.

05sonic4.6 said:

The ptv contact and the follower that came lose happened on opposite heads. Are you saying the machine shop assembly is what cause this or how I assembled everything?

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Most likely the machine shop. You have to break this engine down 100% and completely start over, hot tanking it and all.

Most likely the machine shop. You have to break this engine down 100% and completely start over, hot thanking it and all.

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As much as I hate it, I think there is no ovoiding it. She's gotta come back out and come apart.

It looks like a timing issue to me.

Yeah, I'm inclined to believe that the cam timing gear wasn't installed correctly and if it was a tooth or more off, that was enough to cause piston to valve contact. The valves will bend at their weakest point which, in this case, seems to be higher up the stem rather than at the base near the valve head.
PTV contact can cause secondary damage to the rod bearings so, as you've already figured, you have a complete engine teardown and rebuild on the agenda.

Dino Dino Bambino said:

Yeah, I'm inclined to believe that the cam timing gear wasn't installed correctly and if it was a tooth or more off, that was enough to cause piston to valve contact. The valves will bend at their weakest point which, in this case, seems to be higher up the stem rather than at the base near the valve head.
PTV contact can cause secondary damage to the rod bearings so, as you've already figured, you have a complete engine teardown and rebuild on the agenda.

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How can a piston bend a valve on the top side of the head at the valve spring? None of the pistons have witness marks save one, which could easily have been caused by loose parts holding the valve open.
I would even wager that particular valve has a bend head, while the rest do not.

RocketcarX said:

How can a piston bend a valve on the top side of the head at the valve spring?

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Incorrect cam timing with the rocker still going down as the piston is approaching TDC perhaps? I may just be clutching at straws here to find a logical explanation for what went wrong with the OP's engine. An autopsy might hopefully reveal more information and I'm eager to hear what you find.

Pulled the heads apart today to better asses the damage and they're pretty much wiped out. 10 bent intake valves and 7 bent exhaust valves along with multiple cracked or completely broken guides. So I'm thinking a piece of a guide hung up that one intake valve like rocket was saying. called a shop to get an idea on the cost to repair and just from what I told them it'll be damn near 1k to fix. Valves for these things are not cheap.

So I'm in the market for heads if anyone has any! I'd like to find a nice ported set if I could even made a wtb thread.

Anyway this motor is deffinitly getting a full tear down, I'd hate to have a piece of a guide fuck anything else up once I get new heads.

Been a few years but you used to be able to buy FRPP stage 2 heads for about $1K each I believe. Bolt them up and go. Check with Livernois.

Sure looks like timing assembly error.

Been a few years but you used to be able to buy FRPP stage 2 heads for about $1K each I believe. Bolt them up and go. Check with Livernois.

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Just looked at there site, doesn't look like they carry frpp anymore just there stuff, and there cheapest heads are 2600 plus 2000 to buy them outright without a core! That's crazy money.

Sure looks like timing assembly error.

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I can't deny it's possible that I fucked something up, so let's say theoretically that the timing was off. How could that bend the valve stems with no ptv contact aside from that one valve?

$1200 with just over 100K miles
http://www.ebay.com/itm/2009-Ford-Mustang-4-6L-Engine-Motor-8cyl-OEM-110K-Miles-LKQ-152817747-/192267469962?fits=Year%3A2009%7CModel%3AMustang&hash=item2cc408c48a:g:xVQAAOSwR4FZhMpI&vxp=mtr

There is also one for $1400 with 93k miles from LKQ.
http://www.ebay.com/itm/2009-Ford-Mustang-4-6L-Engine-Motor-8cyl-OEM-93K-Miles-LKQ-149686228-/192277597097?fits=Year%3A2009%7CModel%3AMustang&epid=884582424&hash=item2cc4a34ba9:g:UvkAAOSwtGNZkgva&vxp=mtr

Both have a 6 month warranty, plus you prolly have a local LKQ that has one near enough for you to avoid the shipping if need be.

one and done, my friend.

If my motor wasn't "built" I would just throw another stock one in it, hard to argue with those prices and warranty

Hell I'll keep an eye on them if I need to replace the engine in my truck. Lol