How much current (ampere) draws she at idle and while driving?
- Thread starter goldNSX
- Start date
I would think that the draw would me minimal since the only thing using electric is the fans. The compressor is driven by the motor.
Ignition system? Fuel pump? Injectors? Fuel pump is probably on the order of 2-4A at idle, not much more than that at cruise. Injectors run over 6A each, but of course they might only be firing 2% of the time under light loads...maybe 1A across the 6. Ignition system...just a guess here, maybe 3-4A? Various sensors and such don't take much, but the O2 sensor heaters each use about 1A each. I would guess everything at idle would be 9-13A. You could measure the circuits individually with a 10A meter, just be sure to leave the starter motor out. :tongue:
20 to 30 amps
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Yes but I think about the NSX being equipped fully with electronics.
We have:
ignition system
fuel pump
ECU
TCS
ABS
climate control, fans (you mentioned)
when hot: radiator cooler
With the lights on 15 ampere
add break lights + 7 ampere
add full light + 10 ampere
That is up to 32 ampere only at night.
The alternator is giving about 90 ampere above 2k rpm.
According to this info (sorry only in german) http://www.espa-system.de/funktion.asp a german inventor found a way to save reasonable fuel in the alternator. This is TüV-proofed and NO BS (or was it TüV-proofed BS?
no, it's not). The alternator gives most of his current above 1.7k engine rpm. At engine rpm 8k the alternator wines at rpm 20k! heading in a lot of loss. BTW BMW use an ELECTRONIC waterpump in their cars to save fuel. THE GENERAL IDEA is: why should the alternator wine at 20k rpm if he can do the same job (current) with 3k rpm? So the german inventor uses a larger pulley on the alternator to bring the alternators rpm down. His pulley is DOUBLE the size of the original.
The downside (mainly due to his large pulley size) of this is that the battery must help the alternator below 2k engine rpm which is not favored for people driving mainly in stop-and-go-traffic but is of no importance for people driving on highways most of their time.
NSX: At idle the alternator is wining at the 2.33 rate of the engine, therefore 2.33*800=1864. From the Service manual the alternator is capable of delivering about 55 ampere. At 1700 engine rpm the alternator reaches 80 ampere. If the alternator is not capable of delivering enough current the car needs (lot of electronic ON) the battery must help here which could be critical if you use an Odyssey.
If I would use a pulley that is 1.25 times larger (to be on the save side) than the OEM one the alternator would deliver about 40 ampere at 1500 alternator rpm. On the other hand at 8k engine rpm the alternator has now 16k rpm instead of 20k which should be less restrictive on the power delivered.
Crazy idea I know but don't blame me. Changing the pulley is easy. Stranding somewhere out of nowhere isn't.
I read that wrong I thought he was just refering to the AC system.... I need to get some caffine.:redface:
Yes but I think about the NSX being equipped fully with electronics.
We have:
ignition system
fuel pump
ECU
TCS
ABS
climate control, fans (you mentioned)
when hot: radiator cooler
With the lights on 15 ampere
add break lights + 7 ampere
add full light + 10 ampere
That is up to 32 ampere only at night.
The alternator is giving about 90 ampere above 2k rpm.
According to this info (sorry only in german) http://www.espa-system.de/funktion.asp a german inventor found a way to save reasonable fuel in the alternator. This is TüV-proofed and NO BS (or was it TüV-proofed BS?
THE GENERAL IDEA is: why should the alternator wine at 20k rpm if he can do the same job (current) with 3k rpm? So the german inventor uses a larger pulley on the alternator to bring the alternators rpm down. His pulley is DOUBLE the size of the original.
The downside (mainly due to his large pulley size) of this is that the battery must help the alternator below 2k engine rpm which is not favored for people driving mainly in stop-and-go-traffic but is of no importance for people driving on highways most of their time.
NSX: At idle the alternator is wining at the 2.33 rate of the engine, therefore 2.33*800=1864. From the Service manual the alternator is capable of delivering about 55 ampere. At 1700 engine rpm the alternator reaches 80 ampere. If the alternator is not capable of delivering enough current the car needs (lot of electronic ON) the battery must help here which could be critical if you use an Odyssey.
If I would use a pulley that is 1.25 times larger (to be on the save side) than the OEM one the alternator would deliver about 40 ampere at 1500 alternator rpm. On the other hand at 8k engine rpm the alternator has now 16k rpm instead of 20k which should be less restrictive on the power delivered.
Crazy idea I know but don't blame me. Changing the pulley is easy. Stranding somewhere out of nowhere isn't.
Many stereo gurus doing alternator upgrades have done pulley wheels swaps in the past to get more current out of there alternators when going for a larger one was not possible.
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- Messages
- 6,898
Remember, with a larger pulley the alternator givs less current at low rpm. Stereo gurus need much more current.
- Joined
- 15 May 2004
- Messages
- 6,898
You know what I meant. .... .. .....
:biggrin:
Yes. Interesting. With a smaller pulley you won't get more current out of the alternator according to service manual page 23-100 +-2.
