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underdrive question

  • Thread starter Thread starter 95Monky
  • Start date Start date Jan 19, 2010
9

95Monky

Member
Jan 3, 2003
179
0
17
Chico, CA
Jan 19, 2010
#1
  • Jan 19, 2010
  • #1
do under drive pulleys cause the charge light to come one? 93 gt
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Jan 19, 2010
#2
  • Jan 19, 2010
  • #2
They can if your alt is weak, they slow the alt down.... I prefer to put the underdrive crank, overdrive water and leave the stock alt pulley on.
 

faststang90

10 Year Member
Nov 5, 2007
522
16
49
baytown texas
Jan 19, 2010
#3
  • Jan 19, 2010
  • #3
i have ran the race crank pulley on most of my cars and i added the newer alt and have not had a problem. when i had the stock alt on it i had to keep the rpms up
 
9

95Monky

Member
Jan 3, 2003
179
0
17
Chico, CA
Jan 19, 2010
#4
  • Jan 19, 2010
  • #4
I'm not sure what pulleys are on it, but it has no smog or ac. The car was being set to road race and the owner lost interest. It has a 95 alternator on it. I am guessing the alt is going out.
 

faststang90

10 Year Member
Nov 5, 2007
522
16
49
baytown texas
Jan 19, 2010
#5
  • Jan 19, 2010
  • #5
this is the race crank pulley. i did the 130 amp on it to

View attachment 232747
 

nero6

Member
Aug 30, 2007
94
0
6
Jan 19, 2010
#6
  • Jan 19, 2010
  • #6
If you have underdrive pullys I and the charge light is coming on I would not assume that the altenator is going out. Depending on the type of pullys and what kind of set up you are running you may be able to run the underdrive pullys with no issues but I had nothing but problems with mine. The car wanted to stall at almost every stop light and I would not even think about trying to drive it at night with the lights on, it would cut out at every stop unless I kept the rpms up coming to a stop. I checked out my altenator and battery and both were fine. I took off the underdrive pullys, went back to stock and have had no issues since. Some solve the issue by upgrading the altenator to a larger output, but it was not worth the hassle and price for me for the extra few hp.
 
9

95Monky

Member
Jan 3, 2003
179
0
17
Chico, CA
Jan 19, 2010
#7
  • Jan 19, 2010
  • #7
nero6 said:
If you have underdrive pullys I and the charge light is coming on I would not assume that the altenator is going out. Depending on the type of pullys and what kind of set up you are running you may be able to run the underdrive pullys with no issues but I had nothing but problems with mine. The car wanted to stall at almost every stop light and I would not even think about trying to drive it at night with the lights on, it would cut out at every stop unless I kept the rpms up coming to a stop. I checked out my altenator and battery and both were fine. I took off the underdrive pullys, went back to stock and have had no issues since. Some solve the issue by upgrading the altenator to a larger output, but it was not worth the hassle and price for me for the extra few hp.
Click to expand...

Maybe the problem but I'm not sure.. This a car i am looking at buying so... It has a better than factory alt on it I am told aka 95 5.0 alt. Fox body cars are new to me so I don't know all the ins and outs.
 
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