it only happens when the clutch is pressed in all the way. it sounds like a loud knocking noise and gets faster with RPM so I figure it must be my clutch. I just put it about 4 weeks and just now have gotten around finishing the motor up. I havent taken it for a test drive yet since my rearend was having gears installed. what could this noise be.

 

Does it have a dull knocking sound as if
the crankshaft is hitting the block when the clutch pedal is pushed in? Does the crank have an abnormal amount of endplay?

 

it is a knocking sound but the motor is brand new with no miles on it