Speed changing in Final Cut

use the time remapping, that way you can control what part of the clip you want at what speed, and when the speed changes, its very smooth.

what i do is i cut up the clip and then speed up the indavidal clips
so if it was a line there would be normal speed for the jump/rail and then  cut  it for the middle part and speed it up but right cliping and going to duration or speed under the toolbar 

yeah I dont think you are understanding what I am asking. I know how to change speeds of clips. I want to know if there is a way to go back after you have made an edit and change the speed of a clip in the middle of the edit without throwing off all the other clips. For example if you had a 2 minute edit and there was a 5 second clip 30 seconds in that you wanted to speed up to 200%, yet leave all the clips after that clip in their same position so there would be a portion of blank space between the newly sped up clip and the other clips, rather than having the other clips jump up so their timing was off, how would you do that? or is there a way?

i think you just have to turn like auto-snapping or something like that off... not really sure i've hardly used FCP. i think that should do it though, although thats definitely not whats it called.

if u click ont he first clip that u want to move and then hold shift and go to the last clip still holding shift and then click it will select all of it

then u can move all of it

the only way to avoid pushing everything in the timeline down is to use a replace edit where you adjust the speed in the viewer first before putting it in the timeline. 

if you want to remap and get the best effect of it use AE or Motion 3