Upgrading to a 250 amp Alternator (long)
08-15-2008, 05:42 PM
#1
Pro
Thread Starter
Upgrading to a 250 amp Alternator (long)
I moved to South Florida about a year or so ago and immediatly knew I would have to upgrade the radiator on my 2000 as my temps were getting to high for my comfort level. I purchased the Dewitts rad with the twin spal fan setup. Immediatly my old tired alternator started taking a dive every time the fans were on with the headlights and air conditioner. I made the best of it for a while by turning off the air at red lights etc.
I was shopping for a alternator and went to Auto Zone and bought a 110 amp reman unit for a decent price and as soon as I installed it I got charging system fault errors over and over. I returned it and got my core back and was back to the same old thing, and started reading up on the forum about my situation. I learned how the Corvette alternator was special with a computer monitoring system that was looking for 110 amps to be compatible with the computer. I also learned in 02 or so they upgraded the alternator to a 140 amp. In order to upgrade you would have to have your pcm flashed. This was not a option for me because of having a Lingenfelter tune on my Magnacharger. I researched some more and found Nations Starter and Alternator was making a 250 amp alternator that was "Compatible" with the Corvette computer. I was thinking to myself, how can the computer verify it is running at 110 amps when its a 250 amp alternator, so I emailed them asking questions. The owner Adam replied almost immediatly with this:
"The regulator that is used in our high amp alternators is an OEM manufactured regulator. This ensures that there will be no compatibility issues with the system. The factory alternator on the Corvettes is not able to keep up with electric cooling fans and a/c at idle even if there are no extra components. This is a common problem with the Corvettes. Don't be scared about people telling you that a high amp alternator will cause error codes- Ours will not! It's a similar concept to buying a higher CCA battery. The voltage is the same but the capacity is higher. I hope this answers your questions. Let me know if there's anything else I can help you with.
Thanks, Adam"
Anyway, I got it today and installed it. It works perfectly. NO error codes. It has a smaller pully that is made out of billet. I turned on my headlights (110 watt lights with ballasts) the fans were kicking in full blast, I turned up the air conditioning all the way up and then turned up my stereo all the way (5 channel 1200 watt amp). The alternator sat between 12.6 and 12.7 at idle. My old alternator would be at about 7 volts at that point
My emails were answered immediatly and shipping was very fast. Anyway, if you are in the same situation I was in, this the alternator that works. I hope this helps someone!
http://www.nationsautoelectric.com/h...-corvette.html
I was shopping for a alternator and went to Auto Zone and bought a 110 amp reman unit for a decent price and as soon as I installed it I got charging system fault errors over and over. I returned it and got my core back and was back to the same old thing, and started reading up on the forum about my situation. I learned how the Corvette alternator was special with a computer monitoring system that was looking for 110 amps to be compatible with the computer. I also learned in 02 or so they upgraded the alternator to a 140 amp. In order to upgrade you would have to have your pcm flashed. This was not a option for me because of having a Lingenfelter tune on my Magnacharger. I researched some more and found Nations Starter and Alternator was making a 250 amp alternator that was "Compatible" with the Corvette computer. I was thinking to myself, how can the computer verify it is running at 110 amps when its a 250 amp alternator, so I emailed them asking questions. The owner Adam replied almost immediatly with this:
"The regulator that is used in our high amp alternators is an OEM manufactured regulator. This ensures that there will be no compatibility issues with the system. The factory alternator on the Corvettes is not able to keep up with electric cooling fans and a/c at idle even if there are no extra components. This is a common problem with the Corvettes. Don't be scared about people telling you that a high amp alternator will cause error codes- Ours will not! It's a similar concept to buying a higher CCA battery. The voltage is the same but the capacity is higher. I hope this answers your questions. Let me know if there's anything else I can help you with.
Thanks, Adam"
Anyway, I got it today and installed it. It works perfectly. NO error codes. It has a smaller pully that is made out of billet. I turned on my headlights (110 watt lights with ballasts) the fans were kicking in full blast, I turned up the air conditioning all the way up and then turned up my stereo all the way (5 channel 1200 watt amp). The alternator sat between 12.6 and 12.7 at idle. My old alternator would be at about 7 volts at that point
My emails were answered immediatly and shipping was very fast. Anyway, if you are in the same situation I was in, this the alternator that works. I hope this helps someone!http://www.nationsautoelectric.com/h...-corvette.html
08-15-2008, 05:50 PM
#2
Race Director
Member Since: Dec 2002
Location: Baltimore suburbs Maryland
Posts: 10,233
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Cool. Little pricey but thanks for the heads up. When my alternator dies I'll go this route, cause I got a stereo too (though my blasting days are over 
)
Does it put any additional drag on things?
)Does it put any additional drag on things?
08-15-2008, 06:06 PM
#3
Pro
Thread Starter
It spins freely just like the stock one when not hooked up. I think it would drag more when under a heavy load, but for racing, everything is turned off so it would probably be the same as stock I guess. The only way to find out would be to put it on a dyno and compair to stock? My next step is a Yellow Optima battery and a larger alternator power wire.
