i have a 350 four bolt main 010 block out of a 70 nova but i think it was org. in a 78 or 79 full size blazerbut anyways, i need to know how tight i should tighting the lifters

 

Welcome to thirdgen.org.

You don't really "tighten" the lifters. The rockers have self locking nuts so that they will hold their position without being "tightened" down. And it really doesn't matter what vintage the engine is - hydraulic lifters are hydraulic lifters.

Basically, a hydraulic lifter self-adjusts to let the valve close completely while remaining quiet (solid lifters have to have a little gap when the lifter is on the cam heal in order for the valve to close completely - when it starts to open again, it makes a clattering noise). In order to "self" adjust, hydraulic lifter needs to be adjusted so that the internal plunger is in the mid-point that it then operates around.

Now, none of that really answered your question, so I'll go through a couple of ways to adjust them:

Method A: Engine not running:
1) Loosen all of the rocker arms. Make sure they're good & loose.
2) Turn the crank until the #1 cylinder is at TDC ("Zero" on the timing tab). Tighten down all of the rockers just until the slack is removed. Keep wiggling the rocker as you go so you know when the slack is removed - you don't want to tighten them too much.
3) Turn the crank 1/2 turn. Tighten down any rockers that are now loose as in #1.
4) Turn the crank another 1/2 turn. Repeat tightening any loose rockers.
5) Turn the crank one more 1/2 turn, tighten any loose rockers.
6) You will find that there are 4 fewer loose rockers with each 1/2 crank turn. If you give it another 1/2 turn, there shouldn't be any loose rockers. Now give every rocker adjusting nut 1/2 more turn in the tightening direction (that puts the lifter plunger at it's mid-point).

Method B: Engine running:
1) Remove one valve cover. Start the engine and let it run at idle. Loosen one rocker arm until it starts to clatter. Then tighten it until the clatter goes away. Give it 1/2 more turn in the tightening direction. Repeat on the remaining 7 rockers on that side. Shut off the engine and replace the valve cover.
2) Remove the other valve cover, and repeat #1 for the other side.

Method B makes a little more mess, but doesn't take any longer, and is arguably the slightly better method.