Is it worth it to spend money on the gt500 take off suspension? I find them on craigslist from time to time for relatively cheap. (alot cheaper then aftermarket parts)

 

This was discussed not too long ago. Have you tried searching in this forum?

The big disadvantage is that the GT500 suspension is designed for a car with a supercharged 5.4 L iron lump in the front and putting it on an aluminum block 4.6 L non SC car results in the front end sitting higher than stock.

The parts which has some benefit are the rear lower control arms as they have stiffer bushings and thus improve wheel hop.