Alternator Sizing -- HELP!
Thread Starter
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Joined: Jul 2003
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From: http://www.mphparts.com 800-364-1975
Alternator Sizing -- HELP!
Hi,
I think the stock alternator on my C5 is 110 amps. http://www.mralternator.com sells both a 160 amp unit and a 200 amp unit. These are supposed to be direct GM bolt on replacements.
Is there anything I should consider when sizing an alternator upgrade? I installed an aftermarket stereo with about 1000 watts and it dims the headlights despite the fact that I have an upgraded battery and 1.0 farad capacitor.
I think the stock alternator on my C5 is 110 amps. http://www.mralternator.com sells both a 160 amp unit and a 200 amp unit. These are supposed to be direct GM bolt on replacements.
Is there anything I should consider when sizing an alternator upgrade? I installed an aftermarket stereo with about 1000 watts and it dims the headlights despite the fact that I have an upgraded battery and 1.0 farad capacitor.
Race Director
Joined: Apr 2000
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From: South Joisey
Re: Alternator Sizing -- HELP! (diynoob)
I would make extra sure that the replacement alternator will fit. I've heard that some, if not all of the bigger capacity alternators won't fit on an LS1/6 without some surgery. Make sure you can send it back if it doesn't fit.
If you try it, please post how things worked out.
If you try it, please post how things worked out.
Pro
Joined: Jun 2002
Posts: 580
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From: Boise ID
Re: Alternator Sizing -- HELP! (diynoob)
FYI I lookes at that site and didn't see a 200amp CS-130D. The CS-144 is not a drop in replacement for the corvette.
I am running a 250amp CS-144 from http://www.alternatorparts.com
Keep in mind that you want to add up all your fuses for your amplifiers, multiply by 60%, and add that to 75% of the rating for your stock alternator. This will give you a good estimate of what you need.
If you listen to your system LOUD all the time, or at idle.. I would use 75% instead of 60%.
Brian
I am running a 250amp CS-144 from http://www.alternatorparts.com
Keep in mind that you want to add up all your fuses for your amplifiers, multiply by 60%, and add that to 75% of the rating for your stock alternator. This will give you a good estimate of what you need.
If you listen to your system LOUD all the time, or at idle.. I would use 75% instead of 60%.
Brian
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Joined: Jul 2003
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From: http://www.mphparts.com 800-364-1975
Re: Alternator Sizing -- HELP! (brianw21)
Thanks Brian,
You mentioned that the CS144 is not a drop-in replacement -- how did you get yours to work in your vette? Thanks in advance!
You mentioned that the CS144 is not a drop-in replacement -- how did you get yours to work in your vette? Thanks in advance!
Pro
Joined: Jun 2002
Posts: 580
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From: Boise ID
Re: Alternator Sizing -- HELP! (diynoob)
The bolt spacing between the CS-130D and 144 is different. The top mount is the same, so in my case I mounted the alternator with the top mount only and the provided CS-130 -> CS-144 electrical connector.
I then drive to a local machine shop when I had an appt and had them make a small bracket for the bottom.
All in all I don't think you really need the bottom bolt, as the belt and the top bolt held it very securely.. but it it came with two from the factory.....
I paid $60 at the machine shop
I then drive to a local machine shop when I had an appt and had them make a small bracket for the bottom.
All in all I don't think you really need the bottom bolt, as the belt and the top bolt held it very securely.. but it it came with two from the factory.....
I paid $60 at the machine shop
Thread Starter
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From: http://www.mphparts.com 800-364-1975
Re: Alternator Sizing -- HELP! (brianw21)
Thanks Brian,
This is very helpful. Just curious, did you upgrade your alternator due to light dimming? I only have 1000 watts on my stereo which I *DO* listen to loud while idling and it dims. Amperage output on these alternators while idling is darn-near pathetic.
The guys in the audio forum seemed to think that wiring upgrades would fix my problem but I'm already at 4 guage for my amps and capacitor so I think it's an alternator problem. Note that I live in FL where my in-car thermometer (the one on the AC) just said it was 101 outside. YOUCH! That kind of heat does NOT help the electrical system, especially since I have to run my AC full-blast!
This is very helpful. Just curious, did you upgrade your alternator due to light dimming? I only have 1000 watts on my stereo which I *DO* listen to loud while idling and it dims. Amperage output on these alternators while idling is darn-near pathetic.
The guys in the audio forum seemed to think that wiring upgrades would fix my problem but I'm already at 4 guage for my amps and capacitor so I think it's an alternator problem. Note that I live in FL where my in-car thermometer (the one on the AC) just said it was 101 outside. YOUCH! That kind of heat does NOT help the electrical system, especially since I have to run my AC full-blast!
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Pro
Joined: Jun 2002
Posts: 580
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From: Boise ID
Re: Alternator Sizing -- HELP! (diynoob)
Upgrading the "big three" has to be part of your alternator upgrade. The stock big three is designed to handle the stock alternator. If you don't upgrade the "big three" you will get dimming as the voltage drops because of poor factory wiring.
It's cheap and easy...
It's cheap and easy...
