I have been looking at the 140amp iceberg rebuild kit from Summit.

My car has two subs and a 400watt amp. I will be adding an aftermarket ignition soon. Also has a redtop Optima battery.

The lights do dim and the voltage drops when at idle with the brakes applied. It is even worse when the heater fan is on.

Do I need a 140amp or stay with the stock 105amp? I need an alternator that pumps out more voltage at idle.

My only concern is too much voltage at highway speeds. I do not want to over load the electrical system.

With the Iceberg rebuild kit, is there soldering involved? If so, I may just buy a completed one.

Thanks!

 

A 140 amp alternater will not pump out more "voltage" than a standard alternator (thats what the voltage regulator does). It will however, give you more amps at idle, which is what you are looking for.

Powermaster sells a nice natural finish, or chrome, or polished one.

 

What about an alternator off of an LT1? They are 140 I believe.

 

Unless you get an undersized pulley it is incorrect to state a 140 has more output at idle. It has LESS until it spins up a little off idle. If you are equipped with a 105 amp stock unit you should be fine. 140 amp units were popular with police package options because of the higher demand from sirens, light bars and high power two way radios. Unless your driving conditions place severe load on the alt from running all the accessories the 105 amp should keep the battery maintained. Also one thing to consider is that higher peak charging currents shorten the life of the battery. A battery with a 65 amp unit for instance will last longer than the same battery charged with a 140. Yes the iceburg unit requires soldering, but it's straightforeward enough. It is common to have a voltage drop with the blower and a bunch of stuff running, but as long as the stock alt is working correctly you should be OK. I might mention www.alternatorparts.com is blowing out new Delco 140 amp units if that's your choice.

 

Since the car gets a severe amp drop at idle with the brakes applied, headlights on and the 400 watt stereo blasting, I think the 140amp is what I need.