VKB-SIM

How do you tighten or make them less easy to move. I put the alien key in the side and turned it but does not seem to do anything

You'd have to change the spring. Check this video for details please.

One last question do they sell strong springs or is it just a matter of change its position as shown in that video thanks

I'm so sorry, my mind was elsewhere. There's no spring to be replaced, just swapping the post (a screw) from Normal to High position and using the same spring. This way the spring gets extended more than on Normal position.

thanks

On my thread below #82 rubber bands works wonders. It sets up a progressive tension that increases the further you push the pedals.
I like it better than the internal adjustment.
But if instead you take apart the pedals to alter the spring placement, remember where all the pieces go (taking pictures helps).