I'm not exactly sure whats wrong with the SLS.. the car is very bouncy(isn't sagging though) and I know the system can get expensive to fix, but before scrapping it I'm going to try switching the hydraulic res, as the previous owner gooped it up with JB weld or something, and its still leaking. I should definitely change the vac pump its making a ticking noise, and I've read some of the air filter wars lol I like the wooshy turbo noises the cone makes. I didn't add one of the first things I did once I got her running was drop it at the shop for 2.5" straight pipe so she sounds great.