no, thats wrong, ive personaly seen a cam that was installed many degrees wrong (several teeth) it did the EXACT same thing.

lets think about this people: he said all the valve springs were intact. this means that he didnt break a valve spring, and the valve didnt drop. what does this mean? this means that valve head fell off the valve stem or the valve ran into the piston causing it to break. i dont know about you guys but ive never ever heard of a valve just falling appart in a motor.

the only thing that could have happend was that the piston ran into the valve. since he said it was under normal driving (and if this is true it means that it wasnt in high rpms and it wasnt a mechanical over rev). so the valve ran into the piston, breaking the valve off. the only way it could have happend is if the cam was installed correct.

to the poster, take off the front cover and take pics of the timing chain, if its not lined up dot to dot you have the solution to your problem. most LS1 cams have the advance ground in, so you dont need to degree them or anything.

 

So when you when you install a cam out of time it only effects the valve events on one cylinder, huh. That seems to be what you are saying. And yes, valve heads can and have broken away from stems before.

 

no, but one of them has to touch first now then dont they. not all springs are the same, not all lobes are exactly the same, not all valves are the same strength. they were probably all touching, but one of them just gave out and broke first.

i dont think there would be a case where you would see the same exact thing happen in all 8 cyls.

 

+1 for a dropped valve.

 

Looks pretty simple.Something got into the cylinder and stopped the valve.I'm guessing the intake valve broke.That is not from a lack of tuning,it's mechanical.If the other pistons have notches from the valves I would say it's lack of P/V clearance.

 

Put some JB Weld on that bitch and you'll be good to go.


Seriously though that sucks man.

 

where all of the rod bolts thight. I have a 99 ls1 and had cam and head work done with stock bottom end. The piston smacked a valve but not that bad.

 

damn dude! that sucks! that makes my stomach hurt

 

my friend installed a brand new gm crate engine in a ws6 and forgot to tightin one 10mm bolt under the air filter box. the bolt worked it's way loose and into the intake it took about a week for all this to happen. the funny thing about is we heard the bolt bouncing around in the intake and we could never figure out the noise until it destroyed the engine. the bolt ended up in the oil pan.

 

10mm bolt under the airbox? There isnt any bolts under the airbox. Even if there was how did if get through the filter? Theres no way a bolt could make it into the intake unless one of the small screws that hold the TB blade on worked itself out. But I doubt that. Your friend had to drop a bolt into the intake, or dropped it in one of the ports on the head.

 

The guys @ the shop already took my car apart.. I did NOT get to see anything! All of my parts were in a box!!!
Once i saw the spring sticking up after they remove the valve covers... I was Sick!! You could almost pull what was left of the valve right through the top of the head!!

Once again... When i p/u my car it had an idle problem...(surging in both park/drive) 700-1000 up... down... Initially i though it would "re-learn" idle.. However, that was NOT the case... When the car "died" there WAS NO KNOCKING.. i was running about 60-65mph... and it simply died... I pulled over, popped the hood, and there was a coolant "vapor" coming from the air lid...??? i "assumed" that it maybe had an intake leak and possibly crapped out my MAF...

After 4 hours of waiting on a flat bed wrecker.. i finally got the car to the shop.. The mechanic came out... attempted to start my car and it was @ that point that it started knocking.. NOT banging... simply knocking.. the owners were @ lunch.. I was SO pissed ( motor was just built) & had not had anything to eat, so i walked to get a bite and VENT to myself... It was upon my return that one of the owners said.. "It's locked up"... I'm like WTF????

The heads are LS6's(243) out of my brothers Z06... they had "maybe" 3Kmi on them.. I had a local guy,,"hand port" the heads & upgrade to the Patriot Dual Golds.. & yes the valves were stock... I DO NOT race my car.. persay...

For the few days that i had it... i NEVER took it above 3500-4000 rpm... I NEVER heard any kind of detonation... I will say that the day of... when i first cranked it up that morning... it was hesitant when turning over...

Lesson learned.... I will have LG Motorsports build my next motor @ the first of the year... Maybe sell my current cam 232/236 595 601 114 ( comp) & upgrade to the G5 series...

THANK YOU ALL for your thoughts, replies.... I "truly" appreciate them..

 

IF it was running lean (surging) its possible that the guide got so hot that it ceased the valve then the piston hit the valve and broke it off.
Sorry to see it.