Lucas Stablizer is used to 1 extend the life of your oil, and to to help protect parts. Were as normal oil pretty much drains off the engine, Lucas leaves a fine coat to protect, revitalizes seals and makes starting easier. Basicly the same as Slick50
but better. You can not gain HP from a tune-up but you can increase acceleration. Autolites are low end plugs. Most people say if you use platinum or iridium plugs you get a better spark, which leads to better acceleration. Everyone has their own opinion on oils, I use synthetic, cost more but I feel it works better. For tranny I use Royal Purple, but there is a new product out called trick shift. I started using it in my wifes car and I can notice a difference with it. Shifts cleaner and on point. They say the wires you can use are OEM, which are made by Denso if I'm not mistaken. I use NGK plugs (iridium IX) and wires. Also about once a year I seafoam my Intake
Now I'm not telling you to go out and change what you have already done, just keep it in mind for the next time. Platinum and iridium plugs start at about $5-6 EACH and run up to about $15 EACH, so it can get expensive. Lucas products are also expensive, but well worth it.
If you want to free up some HP you might want to look into hyper grounding your engine.