If your timing is 180 degrees out and you turn the motor will bend valves?

If your timing is 180 degrees out, it is very likely that you will bend valves when you turn the motor. This is because the valves will be open when the piston is at the top of its stroke, and the piston will hit the valves as it comes down.

To avoid bending valves, you need to make sure that the timing is correct. This can be done by using a timing light or by following the instructions in your vehicle's repair manual. If you are not confident in your ability to do this, you should take your vehicle to a qualified mechanic.