SSnakekiller

iTrader: (8)

Have a friend with a built 441 stroker LS7. Was running fine a couple days ago but was blowing a lot of white smoke at WOT upon letting off the gas. Over the past couple days it hasnt been running too bad but now all of a sudden this bad slapping noise.

Is it a rod?

Valvetrain?

http://www.youtube.com/watch?v=fwSCM...ature=youtu.be

"MAC"

iTrader: (1)

hmmm id say its a rod my car didn't sound like that when my lifter went bad but im not a mechanic and im not too sure but best guess from me is a rod. sorry bout your motor and good luck with the responses.

Know_It_All

Pull a valve cover and take a peak. Look for anything that's loose.

Blackpanther99

iTrader: (8)

Hope its not a bad piston! Do that^

Albertan

That unfortunately sounds a lot like the spun rod bearing in my son's old Cavalier. It sounds like it is coming from everywhere. Pull valve covers off
as has been mentioned, maybe you will be lucky. Also could drain oil and have it analyzed see what they find. It will be either bearing material or piston.

KevinR

Not good. It doesn't sound like that's valve train related. Sounds more like you have a bent a rod or spun bearing. White smoke normally=water. drain the oil and see what's in it. Look for metal shavings. If they're gold, then you've spun a bearing. Just see what you can find. Good luck.

Kooljames20

iTrader: (9)

it could be a dropped valve thats kind of how my car sounded its just hard to tell in the video

SlowBurn

iTrader: (7)

Pull the pan and check for chunks/shavings. If that's good, do a leak down test.