Underdrive Pulley on Altenator?

[93gtmustang]

I have BBK underdrive pulleys on 93GT Mustang.
My alternator does not seem to be charging as well lately. Especially when my electric fan starts running alot.
If I put my old alternator pulley back on will that help? I think my alternator is the stock one.
And also, will it affect anything running the BBK underdrives with a stock alternator pulley?
I really don't want to dish out money for a 3g PA Performance alternator at the moment.

 

[AnthonyR23]

I got a overdrive pulley for my 3 g alternator... and I'm charging great.. you could do the same with your old alternator... summit racing has them for about 18.99. I did that with my underdrive pulleys... only thing is my belt is a little loose so I need to get a new one... u may be ok though.. I'm just leaving mine for now... just squeeks a little at startup but then is fine... may just need to wear in though...

 

[AnthonyR23]

I know you mentioned not wanted to dish out the money for the new alt. but honestly I would put that next on your priority list... especially with that electric fan and if you ever want to run a amp for speakers... nothing worse than getting stuck in a parking lot with a dead battery!!

 

[93gtmustang]

This car has no stereo and never will, and it is used mainly for drag racing.
My main question was, that if I put my old stock pulley on my alternator, would that screw anything up running the stock pulley on the alternator with the other BBK underdrive pulleys I have on.
Thanks.
I know I should get a 3g . I just want to buy a little time.
The alternator always charged good for what I do with the car. The only thing I've done is replace my taillights with lx taillights. I can't seem to think that that would effect anything. I also put a stock air box on in place of my conical K&N. Maybe I hit some wires on the alternator. It's still charging , but not even half as good as it use to.
I put a new battery in last fall, so it's not that. I use to be able to leave my key on when I was setting my TPS , for quite a while sometimes I'd forget to turn it off, and the car would start right up. Now , for 2 mins., and the car won't start.
Thanks

 

[AnthonyR23]

I doubt you'll have a problem putting the old pulley on... allot of people do that!!

 

[PJB]

Ive got the stock alternator pulley and underdrive pullies on the waterpump and crank on my car.
The alternator just wouldnt charge with the underdrive pulley on it, even with a 130 amp 3G alternator.

 

[Mustang5L5]

I run an ASP Overdrive alt pulley on mine. 1 7/8"

$20 from summit

 

[93gtmustang]

So there won't be a problem running my stock pulley on the alternator with my underdrive pulleys or running an overdrive pulley with the underdrive pulleys, right?
Thanks

 

[Mustang5L5]

None other than having to get another belt

 

[AnthonyR23]

you probably can use the old belt.. but the squeeking at start up may start to get to ya!!! I haven't got around to replacing my belt yet... just got a new one cause I got rid of my a/c.. then after the e-fan and new alt.. that's when I realized I still needed more juice.. I got my overdrive pulley from summit too... Definitely worth the 20 bucks!!!

 

[gambit90lx]

alternator

yeah i bought a jegs 1 wire 100 amp alternator and i have underdrive pulleys and also a big amp for my speaker and i am still having charging problems any suggestions...its like it isnt putting a charge back into the battery when its idling...

 

[91 HATCH]

This car has no stereo and never will, and it is used mainly for drag racing.
My main question was, that if I put my old stock pulley on my alternator, would that screw anything up running the stock pulley on the alternator with the other BBK underdrive pulleys I have on.
Thanks.
I know I should get a 3g . I just want to buy a little time.
The alternator always charged good for what I do with the car. The only thing I've done is replace my taillights with lx taillights. I can't seem to think that that would effect anything. I also put a stock air box on in place of my conical K&N. Maybe I hit some wires on the alternator. It's still charging , but not even half as good as it use to.
I put a new battery in last fall, so it's not that. I use to be able to leave my key on when I was setting my TPS , for quite a while sometimes I'd forget to turn it off, and the car would start right up. Now , for 2 mins., and the car won't start.
Thanks

im with you on the no stereo it is just more pounds on a light car.use the stock pulley and check for bad connections

 

[91 HATCH]

yeah i bought a jegs 1 wire 100 amp alternator and i have underdrive pulleys and also a big amp for my speaker and i am still having charging problems any suggestions...its like it isnt putting a charge back into the battery when its idling...

you need to get a couple 1.0 or larger capacitors and a overdrive pulley with a better alternator as in 200 amps or more but look for one that puts more out at idle

 

[93gtmustang]

I just checked the connections to the alternator.
I tightened up the belt with the belt tensioner.
Checked the battery with the engine off. 12.8 volts
Check the battery with the engine running. 13.8 volts
Brought the idle up to 1000 rpms. 14.5 to 14.8 volts
The voltrage gage in the car is showing that the alternator is definately charging the battery alot better. It's at half way up on the gage from 1000 rpms up.
It's at the line below half when the car idles normal , about 750-800 rpms.
This is the way it use to be with the underdrive pulleys.
All I can figure is that I may have hit a wire on the alternator causing it to not to work at 100 percent. Or, the belt may have stretched some from the weather going from cool to hot. My new engine was installed in the winter, and with the change in temperature the belt may have expanded some. This slight difference must have an effect with running underdrive pulleys.
So far so good!