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I've been raping with the Auzzy mexers about putting in an isolator for my alternator to increase H.P., and I thought I'd throw the desiccation open to the rest of the world to get some more input. Could you click on this and tell us what do you recon about the idea?
Thanks ;)
Mr. MX6
 

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Shutting down the alternator isn't a new idea. Drag racers used to do this all the time to eke every last ounce of speed out of the car.

You don't need to switch the heavy lead from the stator output: you can switch the relatively low-current field supply off (open) to disable the alternator.

The gains won't be that much of course. At it's maximum rated output of 90A (V6 model), the electrical energy produced is something around 1242-watts nominally. If we assume a low-ball efficiency of, say, 40%, the engine is feeding it something like 3105-watts or about 4.1HP, but this much power is only drained when it's making full output power. This kind of output is required when the wipers are running fast, the headlights are on high-beam, the rear-defogger is on, the blower motor is running and the A/C clutch is engaged...you get the idea. In most driving (especially racing), the load on the alternator is quite low. So if we say the draw is only 30A for most good-weather driving conditions, the power consumed from the engine is just over one kilowatt, about 1.4HP.

Every little bit helps :D
 

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i new some guys that used to take the altinator belt off when they would run. They needed to charge the battery after every run though. The bat would work withought any hp loss for about 40secs on the dino oand freed up around 5Hp.

If yu wanted to do some reaserch you could try and find an Ac cluch to adapt to your alt... You could just hit the switch, open the clutch and the bat would take over.

You might want to go with a bigger battery if you do this.:D
 

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TT-MX6 said:
i new some guys that used to take the altinator belt off when they would run. They needed to charge the battery after every run though. The bat would work withought any hp loss for about 40secs on the dino oand freed up around 5Hp.
Doing this has an added benefit: by removing the belt altogether, you remove the parasitic drag the alternator rotor, bearings, brushes etc present to the engine. This addresses both the electrical and mechanical drags the alternator produces.

I can see a bit more power being added by doing this but again, it's an effort to eke out every possible drop of power and isn't likely something someone would do all the time.
 
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