Alternator question
06-03-2019, 10:59 PM
#1
Racer
Thread Starter
Alternator question
2001 base vert automatic trans...How do I know if I need a 110 amps or the 145 amps?
Popular Reply
06-04-2019, 12:48 PM
An alternator only puts out what the demand of the car is. Unless you have added some high power sound system or other high current draw equipment that exceeds the stock current rating, a larger current capacity alternator will do nothing for you and is simply not needed.
06-04-2019, 06:57 AM
#2
I just changed my alternator to the 145 amp. I have an early 2003 and it had the 110 amp, after my car died on the side of the road for electrical issues, I felt a higher amp alternator was in order. I have a manual car but I'm sure the 145 is fine for the automatic too.
06-04-2019, 10:31 AM
#3
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The older these vettes get , you start to lose amps.
I run a 200 amp with no problems.
I run a 200 amp with no problems.
06-04-2019, 12:21 PM
#4
Racer
Thread Starter
I just changed my alternator to the 145 amp. I have an early 2003 and it had the 110 amp, after my car died on the side of the road for electrical issues, I felt a higher amp alternator was in order. I have a manual car but I'm sure the 145 is fine for the automatic too.
do you have do do anything with fuses because of the higher amps?
06-04-2019, 12:48 PM
#5
An alternator only puts out what the demand of the car is. Unless you have added some high power sound system or other high current draw equipment that exceeds the stock current rating, a larger current capacity alternator will do nothing for you and is simply not needed.
Last edited by v6turbo87; 06-04-2019 at 12:49 PM.
06-07-2019, 06:19 AM
#6
05-01-2023, 04:01 PM
#7
Have you had any issues after upgrading to the 145amp?
Did you use the model with the clutch pulley on your manual c5?
Any issues with the clutch pulley on a manual transmission?
My 1999 manual has a 110amp and thinking of upgrading to the 145amp, if it works on the 1999.
Did you use the model with the clutch pulley on your manual c5?
Any issues with the clutch pulley on a manual transmission?
My 1999 manual has a 110amp and thinking of upgrading to the 145amp, if it works on the 1999.
05-01-2023, 06:54 PM
#8
Originally Posted by Jeffreydd;[url=tel:1606578243
05-02-2023, 01:57 AM
#9
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05-02-2023, 05:23 AM
#10
Originally Posted by Jeffreydd;[url=tel:1606578455
1606578455[/url]]Why do you need the extra amps? Aftermarket stereo?
The reason I need a replacement is one of the brushes broke. An alternator rebuilder suggested a $30 rebuild kit or replacing with the 145amp version.
Original 24 year old Valeo alternator with 65k miles, is it worth rebuilding? New is ~$350+
05-04-2023, 02:54 PM
#11
Based on advice from the forum members I went with AC Delco reman 110amp for $200 shipped from Amazon.
I really don’t need the extra amps, no need to introduce other issues.
thanks all
I really don’t need the extra amps, no need to introduce other issues.
thanks all
05-05-2023, 08:20 PM
#12
Instructor
Remember V=IR. If the voltage across the battery and the resistance stays the same, the current in your circuit stays the same regardless of the alternator current rating. The only way it will go up is if your voltage regulator fails.
The following 2 users liked this post by PlanoLeMans:
averagejoesautos (05-06-2023),
HT99 (05-05-2023)
05-06-2023, 09:23 AM
#13
Instructor
I'd stick with 110amps unless you plan on adding a Amp/Sub combo and additional power ****** that need the amps. Just responded to another fellas thread about IPC messages about "Charging System faults" with an HO alternator. As the fella above noted...the VR is gonna command the alternator to put out what the car needs...and nothing more [up to capacity]. Whats the point of a 145 Amp alternator if the cars only commanding 90 taxed out with everything on. Save the money and buy beer 
The following users liked this post:
HT99 (06-17-2023)
05-06-2023, 10:51 AM
#14
Originally Posted by averagejoesautos;[url=tel:1606595838
1606595838[/url]]I'd stick with 110amps unless you plan on adding a Amp/Sub combo and additional power ****** that need the amps. Just responded to another fellas thread about IPC messages about "Charging System faults" with an HO alternator. As the fella above noted...the VR is gonna command the alternator to put out what the car needs...and nothing more [up to capacity]. Whats the point of a 145 Amp alternator if the cars only commanding 90 taxed out with everything on. Save the money and buy beer