Are compacitors worth the money when you already have a after market alt and a Optima battery. The only reason why I ask is because I only have a aftermarket HU and Speakers. Im gonna be running 2 amps and 2 subs.

 

depends on the amps, how many watts? what brand?

 

i will be runing kicker kx150.2 and the kx500.2

 

watt rating?

 

kx150.2 has 150x2 2ohm max
kx500.2 has 500x2 2ohm max

 

id get a cap. is all of this hooked up and running? do the lights dim severly? Do you replace altenators often?

 

There not hooked up yet i just want to price everything up so im ready. Im running pioneer HU and speakers and everything is good right now.

 

I wouldn't worry about purchasing a cap for now then. Sometimes small electrical problems are can overcomed by running new wiring from alternator to battery and also a new ground strap. Better just to wait to see if you get a problem. I kind of doubt you will have to get one. If you do all the wiring upgrade and it's still a problem you could just buy it from an online source get a good price and most places offer free shipping.