u/d pulleys=poor voltage output

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04-10-2006, 01:24 PM

ptown87

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u/d pulleys=poor voltage output

I want to beef up my audio system but am afriad that if i put in more powerfull speakers i will also need to buy an alternator with higher output. Because of my underdrive pulleys when driving at night with lights and stereo on my voltage drops to the red light line at idle, but never dies or even bogs. I just don't want to buy a new system that kills my car when it hits at idle. What do you think?Anyone else ever deal with this? Thanks in advance!

04-10-2006, 01:29 PM

89GTRed

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RE: u/d pulleys=poor voltage output

Quote:

ORIGINAL: ptown87

I want to beef up my audio system but am afriad that if i put in more powerfull speakers i will also need to buy an alternator with higher output. Because of my underdrive pulleys when driving at night with lights and stereo on my voltage drops to the red light line at idle, but never dies or even bogs. I just don't want to buy a new system that kills my car when it hits at idle. What do you think?Anyone else ever deal with this? Thanks in advance!

the underdrive pulleys re not meant for having a big system draining the alt. if you get a bigger syste than yes i would say you will need a 130 amp alt. because it most likely will bog down w/a new system if it is aready redlining w/ out 1. Good luck

04-10-2006, 01:44 PM

DR8907

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RE: u/d pulleys=poor voltage output

you could run the u/d pullies with a stock sized alt pully - ive heard that works

04-10-2006, 01:53 PM

1fastzook

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RE: u/d pulleys=poor voltage output

If you have a nice sized stereo i woulnt put underdrives on your car.I have a pretty big stereo system and i was droping in the low 10 volt range until i added the second alt.

[IMG]local://upfiles/29615/6672F653F9654A8594856AD462F658C0.jpg[/IMG]

04-10-2006, 01:56 PM

gspfunk

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RE: u/d pulleys=poor voltage output

Honestly, I'd upgrade alt's even if I wasn't going to go w/ a system or U/D's. The stock 85 amp one doesn't cut it for anything aftermarket.

04-10-2006, 01:57 PM

DR8907

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Location: Detroit MI

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RE: u/d pulleys=poor voltage output

I've seen your alt setup before but I never asked about it... did you do it yourself - how hard was it? or how much did it cost to have that done?

04-10-2006, 02:09 PM

1fastzook

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RE: u/d pulleys=poor voltage output

It only took about 1 hour to put on the second alt i used the factory A/C bracket,a peice of angle iron and some spacers to get it to work and im usuing the factory belt.I made alot of dual alt kits for cars at my work and my stang was one of the easiest i ever did.