Bat. drains quickly with system on and car off?

[NorCal66]

...very quickly
Hey guys,
I've got a 66 with a decent system in it and was wondering how most cars can have their systems blaring with the car off for a long time and have enough power to start it later. Is it something newer cars have to prolong the charge or simply that my system draws a lot of power. I can literally sit and watch my cap voltage die in about 2 mins with the volume up a little more than half. I've only got a 70amp alt in there right now, could this the problem? It's gettin real annoying to have to have my car on with it's loud exhaust when I'm just sittin in my car waiting and want the stereo on.
System components: alpine 9805 deck, MBquartz 5.25"(2), MBQuartz 6x9(2), Alpine type s 12 inch subs(2), alpine 5 channel amp f-450, and 1.2 farad cap.
Thanks for the advice, I figure you guys will know a lot more about this than the classic or 5.0 forum.

 

[chrisbudl1]

While your car is running a cap will keep dimming lights, and major current draws, down some. But if I remember right, once you shut your car off, if you run a mega watt system off of just your battery, it will die. The cap needs to charge to release energy, and with out your alternator keeping things charged, you can expect that. I had to start mine just to get a min. of sound at high volume. A battery can only last for so long, more power (system) less time.

 

[NorCal66]

Alright, not just me then. Just seems all my buddies with their newer cars leave their systems bumpin while we're hanging out outside the car or whatnot for quite a long time. Thanks chris

 

[chrisbudl1]

Sometimes at outside parties, my friends would have me pop the trunk and open the doors on my 94 t-bird. I had a poineer cd player, 4 cv 6x8's, and two 12's. I only had 500 watts going to the 12's. I had to specifically get extra gas sometimes. Back then it would only last maybe 5 min, before the battery would die. I just lived with it, but it was on a quiet t-bird.

 

[Stylin Cobra]

buy an optima yellow top battery. that should help.

 

[93GreenLX]

I bought a yellow top and can vouch that it does help

 

[Bloomy316]

...very quickly
Hey guys,
I've got a 66 with a decent system in it and was wondering how most cars can have their systems blaring with the car off for a long time and have enough power to start it later. Is it something newer cars have to prolong the charge or simply that my system draws a lot of power. I can literally sit and watch my cap voltage die in about 2 mins with the volume up a little more than half. I've only got a 70amp alt in there right now, could this the problem? It's gettin real annoying to have to have my car on with it's loud exhaust when I'm just sittin in my car waiting and want the stereo on.
System components: alpine 9805 deck, MBquartz 5.25"(2), MBQuartz 6x9(2), Alpine type s 12 inch subs(2), alpine 5 channel amp f-450, and 1.2 farad cap.
Thanks for the advice, I figure you guys will know a lot more about this than the classic or 5.0 forum.

A stock type of battery and alternator in a 1966 classic is great for very basic "1966" audio systems, but not for what you describe. If you want to provide adequate voltage to your system with the engine off, then you need a more ample battery. And with the engine running you MAY need a different alternator, especially if you have AC, drive at night, etc., and do a lot of high volume listening. And with the engine off, the cap is of no value. And with the engine running, it's an extra load on the small alternator that you have. I don't want to start a big debate about caps, but in my opinion, with the system you have and an adequate alternator/battery, a cap is unnecessary. But it doesn't necessarily hurt anything. Sometimes it's also a help to double check all cables, wiring, etc. Cables and wiring need to be of proper size, and all connections should be secure.

 

[sn1per2121]

my car does the same thing

i have a 68 coupe, im running about 1800watts right now . ive gone through two alternaters and three batteries. im still working on trying to fix the problem , so ur not the only one if i get that fix ill let you know what i did
i u fix it u let me know