Battery light after tune

[ManNmachine]

Since my install of whipple and tune I notice my battery light comes on if my RPMs go over 2500, it stays on for about 30 mins. From what I been reading on here, it looks like my alternator is going bad. I got 4 lbs lower and stock alternator pulley. Should I consider rebuild vs getting a new one, How is the aftermarkets vs one from Ford. If I decide to buy, where could I ordering a new one with the upgraded pulley already installed?

 

[Kwik03DSG]

Since my install of whipple and tune I notice my battery light comes on if my RPMs go over 2500, it stays on for about 30 mins. From what I been reading on here, it looks like my alternator is going bad. I got 4 lbs lower and stock alternator pulley. Should I consider rebuild vs getting a new one, How is the aftermarkets vs one from Ford. If I decide to buy, where could I ordering a new one with the upgraded pulley already installed?

THATS NOT GOOD... THE 4LB LOWER IS OVERDRIVING THE ALTERNATOR. :nono:

you need a 3.2" alternator pulley, and are you sure that the battery light is indicating that its on its way out or just being overdriven... and the motocraft is the best one by far. i rebuilt my stock one, it crapped out, bought PA performance, crapped out, and bought duralast, take a guess what happened, all before i bought another stocker. No problems since...

 

[ManNmachine]

I think the light means its going out because I was running the 4 lb lower with ported blower for about 40,000 miles without problems. Then I upgraded to whipple and tune and days after I left the shop the battery light started coming on. Today I took the car out for a drive and no battery light until about 15 mins into the drive, and it noramlly comes on when when I am going thru 1st-3rd gear, but normally goes out after car been cruising in 6th gear at about 2000 rpms.

 

[Kwik03DSG]

40k miles? wow i wouldnt have expected that... possibly your increased fuel demands with the twin screw upgrade, combined with the fact that the alternator IS on its way out is causing the light to come on.. my only guess as to why now is that mabye your alternator wasnt under as much stress feeding a ported blower combo pump wise... thats just a guess... but ultimately you do need a new alternator, with an oversize alt. pulley.

 

[cobracide]

Start n' Charge or OEM

 

[Kwik03DSG]

start n' charge or oem

+1

 

[ManNmachine]

I am gonna get the OEM with the pulley swap, would 130amp be good enough? I was out last night driving and noticed my ABS and Airbag light came on, I pulled over then the car stalled. Every time I turned the ignition it nothing except a ticking sound like come from the starter. Finally I hooked up jumper cables then it started right up. Drove it home with no problem but now I think its best I invest in alt. I am gonna order from Tousley and get a bigger pulley.

 

[Kwik03DSG]

I am gonna get the OEM with the pulley swap, would 130amp be good enough? I was out last night driving and noticed my ABS and Airbag light came on, I pulled over then the car stalled. Every time I turned the ignition it nothing except a ticking sound like come from the starter. Finally I hooked up jumper cables then it started right up. Drove it home with no problem but now I think its best I invest in alt. I am gonna order from Tousley and get a bigger pulley.

yeah your alternator isnt charging anymore. its draining the battery. that is the same exact issue that happened to me.. except i dont recall the ABS light coming on.. but yeah order from Tousley; Steve's prices are great.

 

[ManNmachine]

40k miles? wow i wouldnt have expected that... possibly your increased fuel demands with the twin screw upgrade, combined with the fact that the alternator IS on its way out is causing the light to come on.. my only guess as to why now is that mabye your alternator wasnt under as much stress feeding a ported blower combo pump wise... thats just a guess... but ultimately you do need a new alternator, with an oversize alt. pulley.

Are you recommending the replacement should be higher amp due to the increase fuel and mods?

 

[ManNmachine]

Does anyone know if a higher amp alternator would over charge the battery or have any other issues? I do not have after market stereo, just what's listed in my mods

 

[Jimmysidecarr]

If you are going OE I do not believe higher amp is an option.

You have two choices that are viable.

A Start-N-Charge or OE, other choices are wasted time and money IMHO.

 

[Kwik03DSG]

Are you recommending the replacement should be higher amp due to the increase fuel and mods?

sorry about that... No its not necessary. the OEM 130 amp one is just fine with the mods listed.

 

[Root1022]

Honestly Jamies Start'n Charge is by far the best alternators for our cars. Check out the last page of the Alternator sticky for his contact info. Talk to Jamie, I promise you wont buy one from anyone else!

 

[ManNmachine]

Thank you all for the support! I'll be picking up an OEM, the work looks pretty easy, but I found a local Ford dealer that will do the labor for about $100

 

[ManNmachine]

I know the 3.2 pulley is recommended for a 4 lb lower, but does anyone know if a 3.5 Alternator pulley would hurt ?

 

[ManNmachine]

I got new motorcraft with 3.2 Alternator pulley, been about 50 miles on it, all was well until I got over 3000rmp and I thought I saw the battery light flickered. So perhaps even a bigger alternator pulley would do the job. My solution is to get rid of that 4lb lower and put stock ring on it, I would rather spend money on other mods like suspension than keep replacing alternators.

 

[cobracide]

I know the 3.2 pulley is recommended for a 4 lb lower, but does anyone know if a 3.5 Alternator pulley would hurt ?

I've been running a 3.5 alt with a 4# lower for over a year with no issues. I did this on purpose to underspin the alt.