gettin confused on lights dimming

A cap will not help your electrical system. All it does is stores energy for a brief period of time and then discharges it rapidly when there is a voltage drop in the alternator output. Ok, I think I know what the problem is. You said that you have a 200amp alternator. Well, at idle, it is probably putting out less then 50amps. What RPM is the alternator rated 200amps at? Do the lights still dim if you are driving agressively? Meaning you are getting the engine near redline often? If not, then we have just figured out your problem. If the lights still dim when you are driving aggressively, let us know, and we will go from there.

Well, then the problem would be alot more difficult to diagnose. When you drive more aggresivly, that allows your Alternator to reach its maximum output potential. If you drive aggressively and your lights still dim, things get a little more complicated. See, when your car/engine is running, the electrical Should Be running completely from the alternator. If you are draining your batteries when the car is running, then your alternator is not powerful enough, but it is obvious that that is not the case here. Now, if you drive normal, cruise at 70mph for 1 hour or 45~55mph for 30 minutes, without revving the engine high in the rpm range, then the alternator is probably not putting out enoughpower. This would result in the battery starting to drain. I think that this may be the problem as it is what happens most often. The problem with High Output alternators, like I said before, is that they are not really usable for everyday driving. They simply do not put out enough amps at lower RPMs to keep all the electronics working. If indeed this is your problem, I would suggest that you get two alternators. Neither of them should be high output. They could both be 100~120amp alternators. This should remidy the problem. Now, an "easier" fix would be to add an additional battery to the system. This would allow you to go extended periods of time without Revving the engine. For the second battery, I would suggest any brand of Deep Cycle batteries. I say Deep Cycle because you can fully discharge them without many adverse affects.

Most high out put altenators put out their peak charge at around 2500 rpm, so you dont need to drive aggresivly, you just need to not sit there and idle. As for caps, their use is fairly simple. When you have a large drain on your electrical system they provide a immediate, albiet, short lived boost. In car audio this large sudden drain is caused by a really hard hitting deep bass note. The cap is simply to help out a healthy system, not fix a sick one.double-secret reverse-osmosis speaker-cone-induced high-level interference distortion, Its a killer