tbi downpipe to manifold springs

[eran tomer]

i've been tightening the nuts on the springs with a torque wrench to 20nM and the springs just kept on compressing without getting to the torque until i stopped myself fearing to make a damage.
they are brand new springs.

 

[GoToGuy]

How far did you go? 14 ft lbs, 177 inch lbs. Unless your torque wrench is out of cal. As you crank it down the spring resistance should increase till it meets the torque limit. The springs are large, what would you damage, the spring rate, resistance increases with compression. And usually the rate is on a curve not a straight line.