Pressing brakes make dash dim?
 

Do the brake lights use a lot of electricity?

Because when I press my brakes, at night all the lights in my dash dim up, and in the day, I can see my clock dim.

Maybe I should make LED taillights

my lights dim as well when i hit the brakes, the stock FC alternators don't produce enough amps at idle to work efficiently.

I get this too, i was getting paranoid about my electrical again.

I used the LED's in the brake/tail lights and it did help a good bit with that little drop in idle speed and dimming of lights. Problem is they aren't quite as bright as the original bulbs. My third brake light is still original though and they are bright enough IMO to be seen easily.

Mine did that when my battery ground was weak. Check your grounds, maybe redo some of them. It will help.

I have brand new upgraded(ie larger guage) ground and power cables and they still dim.

My idle lowers and the dash dims when I turn on the lights, but it doesnt dim with brakes..

S4 alt is lower output than S5. see if you can source an S5 one from a junkyard, or maybe consider an FD alternator.

Silverrotor is selling kits to convert over to the FD. Thinking about doing this- just got an optima red top and figure this is another good way to rid myself of the s4 electrical gremlins.