heres a new question, when looking at my Vafc i notied that when i turn my headlights on my rpm's jump up from 700 to 850 then slowly settle. This would mean that its taking power from the engine right? please now assumptions, only answer if you know.

 

Yes, lights use electricity..........and the battery gets power from the alternator and the alternator has to work harder give the battery that much juice. I dont know if you are talking about electrical power or horsepower. When you turn yer headlights on the battery needs more electricity so the rpms go up for the alternator to produce more electricity. I doubt it is harder to turn the alternator when it is under such loads so it wouldnt effect horsepower.


[Modified by Honda Hick, 5:51 PM 12/2/2002]

 

 

i woulnd't mind knowing what thats about... grow up.

 

WHAT HE SAID!!!!!!!!!

sorry, get over it

 

70 posts and 98%, says it all.

 

you're right!!


im not a big forum guru, just tryin it out.
can u tell me what these percentages are about?

BTW..i see other users with more posts than u, and they have 98% also, so does this make them stupid also?
Your question was just a no brainer for me...I'm sorry i insulted ur intelligence

I'm tryin to learn here...dont flame me....I've had enough...i bow to you!


I'm done...are you?




[Modified by skunkintegra, 9:19 PM 12/2/2002]

 

forget it, point is you were disrespectful. i asked for no recognition, just dont appreciate it when people post useless ****.

 

Honda Hick was mostly correct about - However, the reason that the RPM's jump is the same reason that the RPM's jump if you bump the steering wheel and the power steering kicks in. Under a load, the alternator does require more power to produce the additional amps to power your devices. So yes, it does take horsepower away from your motor. As far as exactly HOW much, I am not certain, but you could do the calculation of:
Amps x Volts = Watts
This is the load being produced, and consequently needs to be generated.

So the final Formula (Amps x Volts) * 0.001341 = Horsepower consumed
This does not take into account inefficiencies, but it will get the general idea.

Lets say that our lightbulbs draw 7 amps each. Your car usually produces about 14 volts or so from the alternator.. so 7*14 = 98watts, *2 (left and right) = 196watts for the lights (just the bulbs, nothing else considered right now)

SO finally 196 * 0.001341 = 0.262836HP used to run your headlights.



HTH!



[Modified by B94Cast, 9:28 PM 12/2/2002]

 

fyi its the IACV (idle air control valve) on the intake manifold that draws in more air when the ecu detects a load.

 

Any increased load placed on the electrical system will be proportionally compensated by the alternator, hence the engine will rev at a slightly higher RPM at idle.

 

the headlights draw power as well as any other lights. You may see your dash and dome lights dim if it were the case.

 

thanks for the replys, its obviously not enought to worry about but i'm think i'm gonna run with my headlights off at the track, hehe