i've got a bad oil leak that i traced coming down the manifold and up to the rear valve cover bolts. I got 1.5 rotations out of the first bolt with out even trying. I want the proper torque so i don't over doit and snap a bolt off or strip one out.

 

they are only 1/4-20 bolts, so torque is only going to be like 5 to 8 foot pounds.
i snug them with a 1/4 inch drive snubby ratchet if i cant get a torque wrench on them.

 

I used to work with a tech. that would go until his little 1/4 drive air ratchet started to feel a load. You could almost hear it. It was probably 10 foot pounds. For the valve covers you have to make sure it goes on flat and even. I always did the valve covers in three steps; in a circular pattern- hand tight, light force with ratchet, medium force with ratchet. If it's an old engine with stamped steel valve covers, try using those load spreaders that are 3-4" long. They help keep it all flat with tightening it.