Capaciator Question?

hi i have a 2004 grand cherokee with two apline type r 12s that are running through a alpine pdx 1.1000. i am getting getting four jl speakers for my doors that are about 50-70 rms that will run through an alpine MRP-F450 amp. my lights already dim some when the volume is 15+. Will i need a capaciator or a sencond battery if i get these speakers and amp. one standdard battery is enough or not? and if i do need a cap, how many farad cap would i need?

thanks for any answers and help!

Caps are going to make the dimming lights go away, but they aren't exactly going to help solve the root of the problem. Try doing the big three wires, and then upgrade your alternator. You can see the bit about the big three in the faq above. The second battery only is going to help you when your car is off...

what are the big three

Big 3 - This entails replacing 3 wires under the hood with bigger ones
Battery ground to chassis
Battery ground to engine block
Battery positive to alternator (careful - often times it is routed thru the under hood fuse block)


Basically, you replace the dinky wires under the hood with larger gauge cable which enables more power to pass thru them.

Another thing to consider is that your gains may be set too high. I don't think turning the volume past 15 with that jeep's electrical system and your setup should cause headlights to dim.