well, With basic mods (intake exhaust, header) you will see hardly any improvement. usu, unless you are having spark blow-out, you won't see any more power from an ignition amplifier. I put a MSD dis-2 HO on my car a long time ago (before I took it apart), and the only advantage I saw was the built in 2 step rev limiter (that little addition was cool hehehe). don't expect any more than 3HP gain with the msd on a stock motor 'though. you don't really need it. The tach adapter is there to strengthen the trigger signals going to the msd so all the other accessories that run off of that pulse (tach, injectors, etc...) will still operate fine with no CEL action. It's allways a good idea to get a stronger ignition system when you start increasing the power of the motor in large quantities 'though (higher compression, forced induction, nitrous, etc..)

have fun!