chevy 350 timing

Probably.

nate

Forgot to mention, that is ASSuming that the distributor is in good shape... check it for looseness before pulling the front of the engine apart.

nate

It may not mean anything except the ignition timing control is working properly. You didn't indicate whether it is an efi engine or whatever. EFI engines of most designs will bounce around quite a bit if you have not removed the spark connector to take the electronic spark control out of the picture. This is the electronic version of removing and plugging the vacuum advance hose on older carbureted engined. Make sure you are following the correct procedure for checking the timing of your engine in it's specific application. If you do not have a repair manual that describes the procedure, that should be your next purchase. Many repair manuals are available at public libraries to use for free.

Lugnut

Like Nate said, check the distributor.If it is a worn out timing chain and has jumped a cog or two, most likely, the engine won't start anyway. cuhulin

Could be. Could also be slop in the distributor drive or pickup.

Assuming its an old enough 350 to have a distributor... a few more details would help.