Some bolts I just tighten… but critical components I always use a torque wrench… in the past I have used a long series a spanner and calculated the pull I need on a spring balance… but for some reason I could not get the spanner on I have used in the past and its part of an expensive set, so I didn’t want to modify it by grinding… , so had to make a tool… I knew that old spanner and socket would come in one day!
One tip I picked up years ago when I used to build Crossflow race engines was always mark the head nuts/bolts after the first stage torque. I would paint an arrow on them with tippex... then move on to the second stage torque, and then the final stage. then I would check all the arrows were facing the same direction, and if any weren't, I would give them an extra tweak until they did. the rational for this is that it takes much of the varying nut/bolt/washer friction out of the equation and you get an even clamping force.
Of course that's exactly what you do in effect on modern engines, but now in a more refined way with an angle gauge... on a BMW engine I recently worked on the bolts were torqued to 40 NM, then 90 degrees, then another 90... I still put arrows on them! the reason for that is its all to easy to get confused as they need to be puled down in sequence, and there are 20 bolts! its all too easy to forget where you are... and its not like a torque wrench where you give it a click to check! All too easy to give a bolt 90, 90 and another 90, at which point it pings!
