"There are several ways of making free horsepower on most older cars. When an alternator "energizes", and loads down, it can suck up about 8 to 12 horsepower. Don't believe me? Fine. Just listen to your engine lug down 50 to 100 RPM when you hook-up some jumper cables to jump start a friend with a dead battery. That my friend's is the alternator lugging the engine down under a load. If you are racing at night with your headlights on or your battery is a little low... then your engine is being put through the same "load" as you're racing down the track. You can gain this HP back by simply installing a switch in the "field" wire to shut it off. The field supplies the alternator with electricity which energizes it, or basically, turns it on. Alternators need electricity to work, unlike old generators. If you don't allow this field wire to energize the alternator, you have gained a few more ponies. You MUST turn the engine off first and make sure the key is off as well when the switch is turned off, or the alternator will NOT "de-energize". So remember... you must turn the switch off before you start your engine. Once the engine's running and you want to re-energize the alternator, simply flip the switch while you're driving and it instantly turns-on." I grabbed this off of http://badasscars.com/techtips.html#free and I was wondering if someoney had any experience with doing something like this before. I would love to get a few extra hp with a fairly stright forward electrical mod. Thoughts? What about the good an alternator does in maintaining voltage? I'll be adding an electric fuel pump to my car when I go EFI and I'm thinking the reduction in voltage to the pump would be a concern (for example). Impact on ignition?