put some rpms on turbo 6.0 today. now smoking ,gap close on plug, no compression on number 7 and spit oil &water on number 7 side of exhaust manifold .hope just a blowed head gasket. if more 370 here I come. any thoughts

 

Sounds like you blew up #7 piston to me man, and that would explain the plug gap closed up. As far as the oil and coolant, The piston may have took out more than just the bad plug. My old 5.3 that was supercharged, broke the ringland and smashed the plug on #7, but luckily thats all it did, well besides the misfire.

 

Damn sorry to hear that. How much boost were you at? I'd pull the plug, and apply air to the cylinder and see if you can hear where it is leakijg first, but it does sound like a piston went.

 

8 lbs of boost .but i had changed turbo's went from magnum 76mm to a PRECISION 76MM .AND IT WAS LIKE NIGHT AND DAY. GOING TO BUILD 370 forged short block .any ideas please send. would like to talk any who has build there own .i have built a lot of engines .this will be my first gen 3 .any 1 knowledgable i will pay for good advice looking combo to with stand 13lbs -15lbs of boost with meth.

 

Did you open the ring end-gaps on this motor? If you put enough heat into the stock piston, the top ring will end-butt and tear off the top of the ring land. The same thing will happen if you detonate and collapse a ring land. Sounds like that hunk got smashed through the head into the water jacket. Hopefully it was the head and not the block that got damaged.

This is where using forged pistons with proper skirt clearance and ring end-gaps. Different MFGs recommend different clearances. I'd call the piston MFG with the build info and see what they recommend.

 

If you were just seeing coolant, I'd say it was a head or gasket. Lifting a head under boost is not uncommon. If it was just oil, I'd say piston. But, since you are seeing both and no compression (plus it being cylinder 7), I'm afraid it's something really bad.

 

nope stock bottom end .what u guys running for gap on rings

 

looks like I got some rings on number 7 .I stuck scope in cylinder piston was intack. scratches on cylinder wall.

 

Do a leakdown test, that should show if it's passing air by the rings or into the water jacket. If it's bubbling the coolant, you prolly lifted the gasket. If the air gets into the crankcase, the rings are prolly broken. Coming out of the intake or exhaust means you could have tagged a valve. What doesn't make sense is the plug closed up but the piston is intact. Extreme detonation or hydrolok maybe?

 

think cylinder filled water and oil and that closed the gap .this mAy sound crazy but the more i look at plug itS a gentle close on the gap like oil and water closed the gap .if that the case the STOCK RODS are strong as sh.. I will KNOW by monday . i ALSO have virgin stock 05 6.0 lq4 i am tearing down to put FORGED PISTONS IN