Well long story short I blew up my brothers 97 Z28. During a powershift it blew something and started smoking out the exhaust. Took it to a place and they said it was hydrolocked. Anyways its been about 3 months and I just started taking it apart to fix it. I figure eitherway its going to need to be torn down just to know what were working with.

So today I took off the intake and throttlebody, but I noticed that when I first opened the throttle body there were little bits of metal chunks right behind the blades. I figure this can't be good...but what exactly can they be from? Im assuming not part of a rod because it would have to fly up past the piston and through the head to get to the throttle body. So if anyone has any ideas let me know. Im going to try and start removal of the intake manifold on Wednesday and see where that takes me...is there anything I need to watch out for, or keep in mind. I'v already looked at some of the guides people have on the net and they kind just blow over the intake manifold.

Also any guesses as to the damage is welcome. I figure best case scenario a blown head gasket and nothing more, drain coolant from cylinders and replace gasket good as new...but im thinking it will be a little more than that. The previous owner had a reputation for beating the hell out of the car and had N20 on it.

 

Ya destroyed a piston. Just hope that it didn't transfer metal to both head and cyl and ruin the whole thing.

 

think the block is still salvagable? Or is it something you can't tell untill the heads are off?

 

Hard to say until ya see it.

 

Should be pretty ease to tell if you blew a piston once you pull the heads. Does the car have a stock TB? If the previous owner installed a 58mm TB, he could have shaved the intake TB ports and left shavings inside.

 

nope stock, and its rather big chunks, like the size of an eraser head.

 

What it probably did is drop a valve,busted the piston and the metal got in the intake through the intake hole with no valve. Then the metal in the intake get's sucked into ALL the other cyls and f***'s them up. Last one I did like that the block was cracked and both heads were junk.

 

lol your not making me feel better. Why would it drop a valve though?

 

They have a retainer or keeper failure. Especially if it had LT4 springs with stock retainers. Could have been RPM related.
There are several reasons.
Tear it down and see.But that's the only way the metal got in the intake.

 

Bit of an update, found alot more debris in the intake manifold. Do I need to drain the coolant to take off the intake manifold?

 

If ya don't want a big mess.

 

Is this really a problem? I have lt4 springs with stock retainers and ive been fine for about 10k miles.

 

Cost me an engine @6000RPM's. Destroyed the whole engine except the crank. The retainer folded up and looked like a cup what hadn't broke off.

 

well, i guess i will change those out when i have the top-end of the engine apart, because i definatly can't afford a new engine right now.

 

Someones has never taken the IM off before

No need to drain for taking the IM off, but you might as well since you will be pulling the motor anyhow.