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Should I take my u/d pulleys off?

  • Thread starter Thread starter The Green GT
  • Start date Start date Jul 16, 2006

The Green GT

No 13 year olds are safe around me.
10 Year Member
Jan 8, 2006
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99
Louisiana
Jul 16, 2006
#1
  • Jul 16, 2006
  • #1
My car has been acting strange lately. Its been hot as **** here and really humid to top it off. The problem is that if I have my A/C on and am driving, when I stop my volts will drop below 9. My radio will sometimes cut off and my tach gets jumpy. My car never dies because of this, but I had to get it jumped after turning it off with a low charge the other day. Im guessing its the pulleys. Anyone else think its anything else?
 

bill302

Active Member
Nov 2, 2005
2,131
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46
alabama,gadsden
Jul 16, 2006
#2
  • Jul 16, 2006
  • #2
i have the same problems at idle when temps are up. no a/c or radio (i have an amp and subs) while idleing or volts will drop and affect the cooling fan and engine temp rises..i have kept my factory pullys and the only reason i have not installed them yet is my stang is not my daily driver..but is sure was hot waiting in line for 30 mins. waiting to get in the drag stirp...idleing with no a/c or radio in line in 90* heat.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Jul 16, 2006
#3
  • Jul 16, 2006
  • #3
I get the same crap in the summer (no U/D's, but I keep my idle set at 650 RPM). For me it's the large electrical load at night with the AC on (all lights, HVAC fan, cooling fan, etc). My radio would shut off, headlights dim, and clock would shut off. This was at ~10.5 volts
I just up the idle to 850ish to make it go away.

I'd say do the pulley swap (maybe just OD the alt?) and/or up the idle if yours is a little low when this occurs.

Good luck bud.
 

The Green GT

No 13 year olds are safe around me.
10 Year Member
Jan 8, 2006
1,269
19
99
Louisiana
Jul 16, 2006
#4
  • Jul 16, 2006
  • #4
HISSIN50 said:
I get the same crap in the summer (no U/D's, but I keep my idle set at 650 RPM). For me it's the large electrical load at night with the AC on (all lights, HVAC fan, cooling fan, etc). My radio would shut off, headlights dim, and clock would shut off. This was at ~10.5 volts
I just up the idle to 850ish to make it go away.

I'd say do the pulley swap (maybe just OD the alt?) and/or up the idle if yours is a little low when this occurs.

Good luck bud.
Click to expand...
Im not going to change the alt pulley back. The stock one is seriously MAYBE a mMM smaller than the u/d one, but the water pump is huge and slows everything down. Where can I find a o/d for my alt?
 

bill302

Active Member
Nov 2, 2005
2,131
1
46
alabama,gadsden
Jul 16, 2006
#5
  • Jul 16, 2006
  • #5
i changed the pully back to the od and still have problems but if you wan't to try it i bought one from an alternator rebuild shop for $5. you might want to contact some local alternator/starter rebuild shops in your area...if you have no luck pm me and i'll get you one and ship at cost...
 
P

Pennywise2

Banned
May 16, 2006
1,379
1
0
Jul 16, 2006
#6
  • Jul 16, 2006
  • #6
Sounds like your alternator or starter is going bad.
You should get it checked to see if it is bad.
Also you should check your battery to make sure it
is putting out the correct volts.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Jul 16, 2006
#7
  • Jul 16, 2006
  • #7
The Green GT said:
Im not going to change the alt pulley back. The stock one is seriously MAYBE a mMM smaller than the u/d one, but the water pump is huge and slows everything down. Where can I find a o/d for my alt?
Click to expand...
FordFuelInjection.com has good prices on the OD pulleys. I'd link to it but they're site is down (it's a top notch place though).

They have the little crank-vs-alt-pulley formula to make sure you dont exceed the alt's critical speed (15K RPM IIRC).

Mr Smith's alternator upgrade page has some info on O/Ding the alt too (I've chatted with him and he's a smart dude and EE by trade). I think some of his links might be outdated, but he does provide an ASP Part # IIRC (another alternative).

Good luck Eric.
 

WhiteDevil

New Member
Feb 4, 2003
2,717
0
0
San Diego
Jul 16, 2006
#8
  • Jul 16, 2006
  • #8
I sold my ASP Underdrives because i did not want to mess with my super low charging at night time while stopped. Not really worth the 6hp that i elegidly god, although my car did not go any quicker at the track with them on.
 
S

stangz4life

Founding Member
Apr 8, 2002
155
0
16
tampa,fl
Jul 17, 2006
#9
  • Jul 17, 2006
  • #9
well i used to have that same issue with my full stereo setup ...until i got the 200amp chrome powermaster alt. cost an arm and a leg ($469)but hey whats a money pit without money going into it right!
 
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