I've wanted to lower my 1991 Formula, but I have the Dual Cat Converters and my clearance is just about nil now. It scraps just getting it onto a drive-on lift and JUST barely makes it over the post lift setups. If I were you, I would put in the stock springs and SAVE your headers from being squashed

the first time you have to go over a speed bump. I know it looks 100% better lowered, but the choice is yours.