how important is a capicator.?
 

want everyone's suggestions.. im gonna be running my same system in my 95 that i had im ny 88 sse.. but i never used a cap.. i will be running 2 15'' kicker dual 2 ohm L7 subs with 2 kicker sx1250.1 amp's with a 80 amp isolator and 2 batery's ( 850 cranking amps and 1000 cold cranking amp's) each battery... i never had a problem with anything shutting off or my amps going into low voltage but i want to know if i should use some caps for the install on the 95 se.? oh and its a 140 amp alternator..

use caps or not.?
will it give me more power and volume.?

thanks guys...

ur extra battery will help with capacitance. but from my experiance, the biggest difference will be in the alternator. and even tho that is a 140 amp alt, it WILL NOT have that much putput. that is max rated output. it will actually put out 70% of that. so it will be about 100 amps effective. i would suggest a rebuild to boost the ampherage output. that will provide the most difference in your draw on other electronics.

You should at least get a smaller alternator pulley to see if you can charge up everything a lot sooner. It should help the car keep running just fine with a bit heavier power draws.

Our alternator, just lilke our old S1's, don't like to spin too fast as they are.

Best bet is to find an Iceberg kit and do some upgrading to that alternator ;)

where would i find an iceberg kit.? and what amp's would my alternator push out with the kit.. its a 140 amp now..

are those kicker amps 1250 watts rms or max?

Kickers are rated at RMS. What you see as the designation on those amps, are the RMS watts ;)

so going by p=i/e, thats like 180 amps, i think. its been like 5 years since ive used that.



**edit**, but actually, i once used a clamp on amp meter, and my system was drawing a peak of 90 amps. and i have 2000 watts of rms.

those amps are rated at rms IF you have the amount of current to supply the "rated" power at their rated voltage (some rate at 12 volts , while others rate at 14.4). starve the amp of current and you will never reach rated rms power.

keep in mind you have to figure in efficiency when you want to know how much current you amp wants to reach "rated" power.

since it's a class d amp, efficiency is going to be about 80%, depending on design
.

1250/.80=1562.5 (its going to take 1564 watts for this amp to make 1250)
1562.5/14.4=108.5

so what this tells us is that for your amp to produce its 1250 watts, you will need at least 108.5 amps of current and you have to have it running on 14.4 volts, which is supplied while the car is running.

dont go with a capacitor, get your current supply up man! ;)

there actuall 1347 watts rms each.. i have the birth sheets..... each one has been upgraded by kicker each time a new upgrade is available...

Everyone has opinions on caps. This is mine I say go for a cap because the cap is capable of charging and releasing energy much faster than the battery can.
The cap will keep up with the demands of the amps better once the car is started.
One farad of capacitance for each 1000 watts.

The two extra batterys are only gonna help for engine off listening time. Any other time they are just gonna be an extra load on the alternator. Electricity takes the path of least resistance. Why make any thing work harder than it has too.

I would most definatly upgrade the alternator, and most important make sure to use the biggest size cable you can. That much power I would go with 1/0 gauge cable. And make sure you have good chassis grounds.

I may get flamed for this but it is my .02

Tim

Charging a dual battery setup will have no ill effects on the alternator, so long as an isolator is installed as well.

I straddle the fence on the cap issue. It doesn't hurt having it in there, and it does help when the low-notes hit to an extent. I ran one when I ran a HiFonics Samson X and some sub that totally escapes my mind (it was American made though), and I noticed some improvement.

Hope this helps:

http://www.caraudiocentral.net/forum...ead.php?t=1888

Make the bass hit harder. No

Help keep the votage up. Yes
That is what a capacitor does, it stores and releases energy really quickly when your amps need it most.

Tim

I couldn't find this the other day when I was searching, but this was a test done by a an audio tech.

Attachment 37192

This is a real world test that was measured by Richard Clark on a Audio Precision unit to portray what happens with a typical capacitor install.
The main point for those who point out the obvious differences between the Red (cap installed) and yellow (cap not installed)…how much of a dB difference is .1-.4 volts in terms of music? And do you feel you are going to hear this within a car? On with the explaination:

Dark Blue curve---
For our first test we played the system with the engine off and no cap. The result was the purple trace at the bottom. We played the system as loud as we could get it that seemed to produce no audible distortion. This was track 30 of the IASCA disc. It starts off with fairly low level sounds for the first 34 seconds. In order to insure the electrical system was stable we did not start the measurement until we were 20 seconds into the song. This means that our 0 starting point is :20 on the CD counter.
The battery was able to maintain it's voltage just below 12.5 until the loud bass hits at 34 seconds (14 seconds into our chart) At this time it dropped to about 11.5 and had a few large variations due to the music. According to the computer calculations (third chart) the average voltage for this test was 11.7volts. This test was done as a baseline for the following tests.

Yellow curve—no cap
For this test the volume was left as it was for the baseline test. The engine was started. Notice that at low volume the alternator was able to maintain about 14 volts. When the loud music hit the voltage dropped to about 12.5 where it remained
except for a few short moments where it actually climbed back to over 13.5 volts. The computer averaged calculations for the average voltage during the 100 seconds of this test was 12.973 volts.

Red curve—cap added
This test was identical to the previous test except the cap (15 farad type) was added 6 inches from the amp with 4 gauge wire—no relays or fuses. The red curve seems to overlay the yellow except that the actual peaks don’t rise as fast or as high during the brief quiet moments. I feel this would be due to the alternator having to recharge the cap. The voltage on loud passages hovered around 12.5 volts. The computer averaged calculations for this test show the average voltage to be 12.878 volts. I see no meaningful differences with or without the cap. I certainly don’t see the voltage sitting solid at 14 volts. One note I might add is that this was a two thousand watt system driven right to clipping and the average voltage stayed above 12.8 with a stock 80 amp alternator. Under these conditions the battery would never discharge! The green and light blue curves were done just for kicks while we had the system set up. In both these tests we turned the volume up until the system was very distorted. This placed a severe load on the alternator and caused the voltage to dip as low as 12 volts. The curves seem to follow each other so closely that unless you have a good monitor it is doubtful you can tell there are two curves. The average voltage for these two curves were both 12.277 and 12.295 volts. If this volume were sustained for very long periods of time this battery would discharge

15 farad is an excessive amount of capacitance for that system, im suprised to see little to no difference.

but speaking from experiance, and also stated before. with my 2000 watts rms system, i noticed no difference in the voltage drops (lights dimming) when i added a cap, then a battery in the trunk, and then another cap. this totals 3 farads of capacitance and a yellow top in the trunk. and the voltage on the cap displayed about the same results as that test. mid 12v on hard bass.

i did however notice a difference in the light dimming with the upgrade of an alternater. i only went from the 105 to a 140, (which is still not enough amps) but the cap would be at low 13v and sometimes high 12v (12.9ish).

Such low amount of a capacitor, for example 1 farad, will not be enough to properly keep a systems voltage up.

If anything, a capacitor is a crutch, or a bandaid, for an electrical system in need of an upgrade.

If you want to do yourself some good, do as http://www.myvideostore.com/images/c..._l_jackson.jpg did and upgrade the alternator and battery. While your at it, BE SURE to upgrade your alternator and battery cables as well (all grounds and power cable's).

literally LOL, ha ha ha,


yeah, what he said :lol:

I would use dual alts if possible and go for a charging capacity of 280+ amps my .02
a lot bigger difference than a cap.

oh by far better, but idk if anyone has even tried that. it would be cool to see tho.

I've seen well over 10 alt's in an Astro. But that was a competition vehicle. The most i've seen in a daily driver is 3.

ok i miss-spoke, i meant on a H or C body

Well I guess I heard that. I really thought a cap would have more of a effect than it does.
1000 pardons kind sirs. :oops:

Ok alrighty then by bye now.

Sorry for the argumentation guys,

Tim

no apology necessary, freindly debates can breed ideas and breakthroughs,

but really, that was no debate, more of a discussion of input

Yes it does, I was cutting up with all the apologies. I enjoy a good discussion
I just really did think they did more good than that.

Thanks,

Tim

can anyone tell me how to add a second alternator.? i would do it in a heart beat.. :twisted:

well, theres definitely no kits available.

is ur a/c operational?

cuz i deleted mine and had contiplated engineering the alt to fit where the compressor was. i would also put one of the lower frame shields that the later 90's had to keep water out. jsut a thought tho, i havent tried anything. yet.

i do not care for the ac as it will be a music car and the windows would be open for voice or sealed shut for spl and db drag. so no i dont care for or need the ac to work.. plus it dont work as it is. (needs recharge)..