JwT

Sorry about the FUBAR on your engine dude. Looking at the plug I would be very surprized if the block isn't a boat anchor now. You have options but none of them are cheap. It's even worse if your making payments on the car. Summit Racing has a drop in motor but 9K is a big ouch even if it pumps 580hp. You really don't want to buy a motor from G.M. unless your running odds and ends out of columbia, if you know what I mean.

I kinda did the same thing you did, but without the dropped valve. I picked up a second owner with 67k miles on it. Thats a lot of miles but it was a great deal, or so I thought. The car is bone stock so I only had to replace the BCM right away. Then the tranny took a dump, RPM rebuilt it right away OUCH. The clutch and torque tube had to be replaced, Thanks Scoggin Dickey. The brakes were bad, did that myself Hawk pads. Tires were shot, hot damn only $2200.00. It had black wheels on the car so,.....they had to be replaced, you don't even want to know.. And after all the scared Sh$tless dropped valves here on the board, it's down in my shop right now. I'm replacing the heads with a pair of Texas Speed PRC 265's, a mere $3300 with gaskets and other parts. WOW what a deal it has all turned out to be.......

'06 Quicksilver Z06

It could have been worse.

It could have eaten a valve after all of that transmission, clutch, torque tube, brake, and BCM work, and a week after you put the new wheels and tires on it.

As it stands now though, you are at least protected from such an occurence.

tim414

Sucks big time. Sorry for your pain. Hopefully the block is intact.

Keep us posted

tim414

you've had your fair share too my friend. Look at it this way, at least your Z will be refreshed for many years of service.

harrydirty

Care to elaborate which motor you are referring to? Part number?

rzmnco

Wow man, that sucks.

Seeing post like this makes me glad I spent the money to have my valves and guides replaced. In the end it cost way less than a whole new motor...

Dirty Howie

Well it doesn't sound like you windowed the block like most of us

So best of luck in what you find in the teardown


DH

Random84

Anything is possible - including random parts failure, alien heat rays and defective valves shearing off. Given the circumstances (and limited information), I'm thinking its much more likely install error contributed to this premature failure.

We don't know the springs/pressures, install height, cam lift or durations, previous racing or abuse from the prior owner, etc.

Now, if OP comes back and says the springs are good, the geometry is right and its a mild cam, but all 8 guides are 3x the service spec.... Then I'll change my mind. Until then, I'm doubtful that solid stems would have changed anything more in this situation than the mileage before failure (given the apparent skill and attention to detail of the installer). Afterall, ALL of the rocker bolts were rounded off...

That's purposeful determination!

JwT

Can't find it anywhere. Closest would be a Marks Performance, but I think It's an iron block. I be tempted to order the new LS3 with 525hp if the computer would run it.

JwT

You bet, can't get rid of it now. It's just about all new.

Jackal

Well...I tore the engine down today...there was more profanity involved...seems I was too optimistic. I am uploading the pictures now.

Dirty Howie

Afraid to look ...........


DH

Jackal

Ok guys, here is my picture heavy update...

So I got the rounded off rocker bolts off today with a NAPA Auto 8 MM impact socket. Worked wonders, and it didn't break like the Craftsman sockets did.

I pulled out all of the push tubes, and found two that had damage, but I think it was done by a previous failure.



These next pics are an indication to me of a previous valve failure, becuase this is on the oposite side from the current failure.







(nics on the valve cover seat)

I then pulled off the intake manifold, which sounded like a rattle can and a whole bunch of parts fell out:



...a look in the #1 intake port found badness:



I took of the other side's head and found various bits of metal everywhere, transfered from the other side through the intake manifold:



Then I took of the driver side head, only to find a fully polished combustion chamber courtesy of flying alluminium!



And then, I worked up enough courage to look at the damage, which took about 10 mins. to do BTW:



OMFG!!!!!



Can I cry now?





Misc. bits of my POS:





I know that some are interested in what the valve shafts look like, so here are some close up shots:







Now I have a very large paper weight...or I may turn it into a coffee table, im not sure yet. I don't know what I am going to replace it with.

C6z06man

Ahh man sorry to see all that damage. I was hoping for you to have some good luck and be able to salvage most of it. It definitely looks like someone was in that head before. Hopefully you get it all figured out better than ever.

C6z06man

Oh and I'm sure you already know but make sure you thoroughly clean out the intake mani. Don't want to have trapped metal get sucked into the new engine.

z0sicktanner

Sorry to see this OP but I figured the block was toast..I have a set of heads here right now that the exhaust valve head took out the intake valve cut into the vavle seat and into the head an inch deep...your exhaust valve broke off an took out the intake valve. Did you find the exhaust valve head?

Jackal

I did not find the exhaust valve....yet.

Turbosixx

Sorry to see this. I feel for you. This sucks.

z0sicktanner

could be in the intake or airbox...crazy, sorry man...

Just Cruise

What am i lookng at guys if i want to get wcc to rework the heads on mine im concerned now too. I just did headers and cam and dont need engine failure.