Guys I have NEVER done any of this on any of the vehicles I've owned but I read a lot of good things about them...how exactly do these work, how are they applied and what are the benefits and drawbacks if any? What is best for an LT1 car and what is good in just about any car?

 

Seafoam you can put in your gas tank, oil or directly in your TB with the engine running. I usually do it every oil change and seems to keep the engine running a little smoother. You can get seafoam from NAPA for about $7-8. Just remove a vacuum line to the TB and pour some in there while the engine is running. Then when the bottle is almost done, pour the other half in there to kill the motor. This will allow it to sit on top of the pistons. Then take it out for a fun (hard) drive. I'm sure this would benifit any engine.