I was looking through some logs the other day and noticed that my voltage through a run gets to as low as 12.0v-12.1v before shifting gears. Is this normal or do i need to increase my alternators amperage somehow? I haven't had any real problems though i know that if voltage stays higher than my pump can deliver more consistently.

At this point in time i do not want to have to deal with charging my car everytime i make a pass running it just on a battery.

 

matt are you still using the stock alternator man, and a full sized battery or one of the little batts?

 

stock integra alternator with an aem pulley and a stock battery

 

put a stock pulley on it. i have the same thing and mine barely ever drops below 14v.

 

unless the battery is getting weakend

a new battery may be needed man

put a multimeter on the battery with the car running if its over 13.4v its doing its thing if not the alt is weakend

 

i get 14.3 14.4 at idle no problem with a meter and in the logs, as soon as the run starts it goes down linearly till i shift then repeats. I guess I can try a stock pulley first.

 

Also check your alternator connector.my buddy had the same problem and found the pins corroded.I cut the harness,replaced the connector and the problem was fixed.

 

Your battery might be going south as well. When you are at idle, there isn't a huge current draw like when you are running it. If the battery isn't supplying enough current, the voltage will start dropping. I would get rid of that aem pulley if it is larger than stock. That will cause you to have a voltage drop too. Feel free to call or IM and I can give you some more hints.

 

Do hondas disable the alternator during full throttle or are they always charging?

 

All wires are tip top brand new.

 

If it's an issue with being underdriven by different pulleys, it will show up at low rpm, not high rpm.

 

Also make sure your belt is in good shape and tensioned correctly, They sling pretty well at 9K

 

i havnt had any slinging issues. So i guess i need to put the stock pulley on...or is that really pointless? Ill have to find one somewhere.

would an odyssey type battery help? or possibly getting the alternator modded?

 

I'd imagine there is someway you can bench test it to make sure the alternator is under-performing and its not the wiring or battery on your car

 

im running the same voltage 12.0-12.5 on the datalog. no problems at idle 13.5-14.0 voltage. tried bigger pulleys went back to the stock size. im wondering if the smaller size on the damper would change anything.

 

smaller damper would slow the alternator.

 

Did you relocate the battery or is it still up front?

 

Does anyone make a high output alternator?

 

had a similar problem im running a ati damper with a oem alt. voltage would drop at idle 11.5-12v then would go back up during the run to 14v and thats with my battery in the back. Im going to try and run a better battery possibly at red or yellow top....

 

What size is your wiring to/from your battery? That was my problem... I was running a Fluidamper as well... I needed heavier wire.. I can't remember the size I ran.

 

thats opposite of what my car does. Im using an ATI street damper and my battery is not relocated, its still up front.

I have 4 gauge wire running from the battery to the cut off solenoid and then an 8 gauge wire that leads to a distribution block from the solenoid for msd, gauges, fuel pump, etc.

 

we need to remember batteries generally sit between 12.4-13v depending on the amount of amperage that battery comes with meaning it will hold more charge

the alternator puts in a top charge of around 14v thats all it is a top charge not true voltage so when you hit the car, and it starts sucking juice from it it is taking the top charge put.

you need to test the batt with a dmm resting then see what drops to during the rn if it rests at 12.8 then drops to 12.9 your not losing any voltage at all

 

could the altenator be spinning to fast? by slowing it down could it put out more voltage. voltage gets worse as rpm get higher right?

 

Have your alternator checked you might be a internal problem at high speeds such as the voltage regulator,diode rectifier or maybe the stator itself is bad.im using a fluidampr and a 170 ah battery which is about the size of a yamaha raptor battery and have 13.7-13.9 volts from 1000-9500 rpm.

 

heres my log simplified. Its 12.4 at the lowest voltage, marked by the marker.