MAJOR current draw... AHHHHH!!!!!!1!11!

[IgnoreMe 5,000+ posts]

i have ran more power than that on worse power hungry amps than that (all old school class AB) with a smaller alt and didnt have the problems this guy does.

i understand what your saying, but what im saying is the alt is the problem. at idle hes loosing voltage which means the alt isnt doing what its suppose to do.

people have ran big systems on stock alts and just added batteries, but they're alts worked right and would stay in the 13.5-14v range. im sure yours did too, correct?

edit: what im saying is he needs a properly working alt. sure he can use a smaller alt than that 180, but he needs the smaller one to still charge the batteries. not sure if im making sense trying to get my point across.

 

[OoMesKoO 10+ year member]

my buddies is a 130a. itll work for now, if you got some extra batteries, but i would look into either
a) check more places to see if you can get a smaller pulley. i know you said its custom and its the smallest they make but keep trying

or

b) replace the alterstart alt with a different one.

ive noticed the cheaper HO alt's always kick on way to high, to be of any use at idle. my buddies with the stock size pulley would idle @ 12.7 volts or so (basically battery voltage), then as soon as he touched the gas and gained 2-300 rpms, it would up to 14v.

Thats EXACTLY whats goin on with mine! Same **** thing.

 

[IgnoreMe 5,000+ posts]

Thats EXACTLY whats goin on with mine! Same **** thing.

it seems to be a common issue with the cheaper HO alts. they cut on way too late to be of any use.

 

[audiolife 5,000+ posts]

on a sine sweep i would fall into the 11's on voltage but i didnt do that too much lol. the electrical upgrades we had back then were far worse than what they have now. biggest alt you could get was 180 amp (mine was a 120 dual out and 1 upgraded stocker to 115 amp as well as a stocker

 

[OoMesKoO 10+ year member]

http://superpageshosting.com/4alterstartcom/pages/store/skudetail.nhtml?profile=highoutputalternators&uid=10999&returnURL=http%3A//superpageshosting.com/4alterstartcom/pages/common/sitesearch.nhtml%3Fquery%3Dtahoe&catuid=10013

thats the alt.

 

[IgnoreMe 5,000+ posts]

on a sine sweep i would fall into the 11's on voltage but i didnt do that too much lol. the electrical upgrades we had back then were far worse than what they have now. biggest alt you could get was 180 amp (mine was a 120 dual out and 1 upgraded stocker to 115 amp as well as a stocker
bro you gotta understand im not doubting you one bit. in fact i take your answers on my battery questions, that youve responded to, very seriously.

what im saying is yes he can get by with even the stock alternator, but whether it be the stocker or the HO alt, he needs to have 1 of them properly charging the batteries and running the rest of the car at idle. he should not have dimming interior lights and dropping voltage when at idle.

 

[60ndown 10+ year member]

id try a better battery (buddies?), if it doesnt work you know its the alt.

 

[IgnoreMe 5,000+ posts]

http://superpageshosting.com/4alterstartcom/pages/store/skudetail.nhtml?profile=highoutputalternators&uid=10999&returnURL=http%3A//superpageshosting.com/4alterstartcom/pages/common/sitesearch.nhtml%3Fquery%3Dtahoe&catuid=10013

thats the alt.

says 85 amps @ 800 rpm, and thats with the stock pulley that comes with the alt, not even with the custom one you have now.

they are either A: lying or B: you are idling WAY too low for the alt to kick on.

from what i have read the tahoes dont idle @ 800rpm's...and it makes me wonder why you would need a super small pulley to try to get some performance out of the **** thing as well.

 

[OoMesKoO 10+ year member]

Dude your like reading my mind. lol. My tahoe idles at like 500rpm!!

 

[IgnoreMe 5,000+ posts]

Dude your like reading my mind. lol. My tahoe idles at like 500rpm!!

try to see if you can get to a gm dealership and see if they have the ability to raise your idle.

yes, its possible to do that, but sometimes at least with the snap on modus, you can only adjust temporarily without having to program the computer. im sure GM has their own scanner and probably has the ability to permanently raise it.

you CAN try a mom and pops repair shop, bur for something like this, i would go straight to the dealer.

 

[audiolife 5,000+ posts]

if it stays at 14 v with nothing on but drops real low its either a bad battery or the regulator is screwy not hooked up right (that also depends on if it an outboard regulator too lol) im not a mechanic by any stretch of the imagination as i have had loose connection syndrome until my buddy bought a hydrolic car lift..but any more with how tight engine compartments get i dont me with that crap any more lol. worst thing i ever did was i hooked up my front battery to the front output of an alt and it bolted in tight only thing is it wasnt sitting flush onto the alt output. couldnt tell it was messed up until we put it on a lift lol. when you change your electrical around that much EVERYTHING has to be right...i would get the battery tested and if that turned out ok i would look over all the alt connections.

 

[SkatinBassPLaya]

tech question,

what does group 31 batteries mean, and why is it good for car audio

 

[IgnoreMe 5,000+ posts]

if it stays at 14 v with nothing on but drops real low its either a bad battery or the regulator is screwy not hooked up right (that also depends on if it an outboard regulator too lol) im not a mechanic by any stretch of the imagination as i have had loose connection syndrome until my buddy bought a hydrolic car lift..but any more with how tight engine compartments get i dont me with that crap any more lol. worst thing i ever did was i hooked up my front battery to the front output of an alt and it bolted in tight only thing is it wasnt sitting flush onto the alt output. couldnt tell it was messed up until we put it on a lift lol. when you change your electrical around that much EVERYTHING has to be right...i would get the battery tested and if that turned out ok i would look over all the alt connections.

he says it drops low at idle in gear. when in park (basically neutral with no load) hes fine. basically that little drop in rpm's is causing the alt to not charge, but he cant get a pulley thats any smaller than the custom one he has now.

OP: i say, if you can get that idle speed up and keep a constant voltage at idle (see what your voltage is in park, and if you get your rpm's raised make sure it stays the same when in drive), then its time to start adding batts. you will need them for that amp for sure, even with the upgraded alt.

 

[2000LaDe 10+ year member]

buy a new battery. problem solved

 

[IgnoreMe 5,000+ posts]

tech question,
what does group 31 batteries mean, and why is it good for car audio

its just a size. people always suggest g31 batts because they are basically the biggest you can get (yes, you got fat *** RV batteries and shit, but realistically g31's are where its at).

g31 is a specific size, g34 is a specific size, ford used g65 size batts, etc etc.