10secZ-28

when i leave from a dead stop my car knocks. i have no idea what it is. is it something 2 do with the trans? after that i runs fine.

archemedes

could be cracked flywheel, where is the knock comming from?, do abrake stand and see if it still happens (before it breaks loose) if so it's engine or trans, if not it's driveline

10secZ-28

it seems to be comming from the front and sometimes it feels like the rear. when i did a brake standstill it still knocked. once it starts going tho there are no problems.

archemedes

I would guess cracked flywheel, pull the inspection cover and shine a light on it, pay attention around the center bolts.Could be engine also, but drivetrain is eliminated

69z-28

just a shot in the dark but check the torque arm mount. my friend has a 6 speed lt1, and everytime he accelerated from a stop there was a loud clunk. he had no idea what it was, i looked underneath and sure enough his torque arm mount was opened and the bolt was missing where it bolt the two together into the trans. the torque arm was hitting the trans everytime it was underload. just something to check that is an easy fix.