Is this normal for an Amp.?
Thread Starter
Drifting
Joined: Oct 2004
Posts: 1,975
Likes: 9
From: "Philly" Pennsylvania
At this point I have driven the car as a daily driver running errands and making mostly short trips, turning the car off and restarting as many as 10 times a day. Always restarts with no problem cranking & firing right up. My replaced battery must have been the previous main problem, I haven't had to recharge the new battery (yet).
Starts out around 14.1v in the morning and after about an hour with traffic light idling voltage goes down to low 12's during idle. While above idle battery reads 13.2 or 13/3v most of the time. If a longer above idle trip of several miles, will work its way up to 13.8v or in that neighborhood.
I conclude that the underdrive pulley system is the cause of the low voltage readings along with some minor increased amperage draw but don't know if this will eventully cause a problem with the battery again.
Will stop by ECS this week and discuss this and some other minor changes not related to charging.
Thanks to those that responded to my questions.
Footnote - ECS is taking a stock alternator pulley and reducing the diameter a little on a lathe, this should speed it up just a little and offset the voltage drop at the lower idle speeds and throught the range on the underdrive system. The guys at ECS are the greatest.
Starts out around 14.1v in the morning and after about an hour with traffic light idling voltage goes down to low 12's during idle. While above idle battery reads 13.2 or 13/3v most of the time. If a longer above idle trip of several miles, will work its way up to 13.8v or in that neighborhood.
I conclude that the underdrive pulley system is the cause of the low voltage readings along with some minor increased amperage draw but don't know if this will eventully cause a problem with the battery again.
Will stop by ECS this week and discuss this and some other minor changes not related to charging.
Thanks to those that responded to my questions.
Footnote - ECS is taking a stock alternator pulley and reducing the diameter a little on a lathe, this should speed it up just a little and offset the voltage drop at the lower idle speeds and throught the range on the underdrive system. The guys at ECS are the greatest.
Last edited by tsts; Jun 2, 2010 at 07:06 PM.
Thread Starter
Drifting
Joined: Oct 2004
Posts: 1,975
Likes: 9
From: "Philly" Pennsylvania
Final Post/Solution
ECS cut down the diameter of an extra pulley (non-clutch type) and this resulted in a slight improvement in voltage maintenance. Then we sent the clutch type pulley taken from the original alternator and had that one reduced in diameter approx.1/4 inch. Same drive belt still could be used. I am now seeing what I would consider close to stock readings for voltage with the exception being a little bit of extra drop during idling periods. New battery has stayed strong through out this experimentation, I consider the problem solved. No more voltages in the 12's and with increased RPM (driving) readings quickly return to the higher 13's. Now see 14.2v. on start up and takes a while to drop down to the mid to high 13's.
