i know that this might sound like a dumb question but i was wondering if when you are running an amp and two subs does this take power away from your car. kind of like when you drive with the a/c on and it tends to put a little more stess on the engine.

 

it effects its but nothing like the a/c does. Unless you are running some major spl type equipment i wouldnt worry too much

 

Hmmm.... put it this way. At night turn on car warmed up revs sit at say 700. Turn on headlight, revs drop to say 600. Turn on fogs revs drop to say 550. Now if I'm sitting at a light at night with all that on AND I have my system pumping almost full volume my revs will NOT drop any lower. I don't notice ANY difference while driving with all of that. So I'm going to have to say that it's not a big deal. Oh yeah, that's all on the shitty 70amp alternator and stock battery from a 92!(well, obviously not the same battery, but you know what I mean)

 

No, the revs could drop, but only momentarily. Stereos only draw a lot of power when the bass hits hard. That is why your headlights dim a little... it is sucking so much power that there is not enough for the lights.

Is this a big problem? No. Normally you're just stopped and at idle at a stop light... light turns green, you go, and the amp produces some more power.

If it bugs you, have your alternator rebuilt. They could probably get 80-90 amps out of it for like $100 (not sure how much it is to rebuild alternators anymore). But going on the stock one shouldn't hurt anything too bad.

 

They have high output alternators for the "super duper" high end systems..

I used to work in a custom stereo shop and the owner asked me to install a system in his own personal vehicle.. now, this dude was an Alpine dealer and could have anything he wanted installed.. on a short note... The vehicle was a Toyota 4-Runner, six 150 watt amps and six 12" subs, this was one of the prettiest jobs I've done considering the availability of my resources ( this was around the mid 80's when subs were just hitting the scene)....never required a HO alternator and the thing was one of the loudest i've ever heard!..

And his taste of music to pump thru his rig?... Country! Yee-Haw!

 

The only thing I'll add is that running any electrical stuff will cause your alternator to crank. This will put more load on your engine. Therefore decrease your MPG and performance.

That's why when manufactures test their cars for MPG, they can turn off the DRL to get a better reading. Then again, we are spliting hairs here.

If you want something a bit more general. When it goes boom, and your lights dim, maybe that's draining too much power. Advise against it.