Notices
5.0L (1979-1995) Mustang Technical discussions on 5.0 Liter Mustangs within. This does not include the 5.0 from the 2011 Mustang GT. That information is in the 2005-1011 section.

Feedback on underdrives

Old 04-08-2005, 01:56 PM
  #1  
Djs94stang
3rd Gear Member
Thread Starter
 
Join Date: Feb 2005
Location:
Posts: 542
Default Feedback on underdrives

I just put on a set from Steeda (asp racing pulleys reboxed). I installed all 3, crank, wp, and alt. I haven't measured the voltage yet but even without any extra electrical items the voltmeter drops a bit when idling. If I put the headlights on...they dim noticeably at idle and with the brake on (brake lights)..it drops more. Add the blower motor/ac and the volt meter drops a lot. The battery light never comes on but I don't like it.

Has anyone else experienced this....and do most just leave the alt pulley stock? Oh yeah...and the alternator is fine otherwise.
Djs94stang is offline  
Old 04-08-2005, 02:04 PM
  #2  
Demon_Mustang
3rd Gear Member
 
Join Date: Sep 2004
Location:
Posts: 837
Default RE: Feedback on underdrives

No, don't use the stock pulley, because the stock pulley is bigger than the one that comes with the underdrive set, which would make it turn even slower. The alt pulley that comes with the set should be smaller, or an "overdrive" pulley to compensate for the smaller crank pulley. If not, then whichever one is smaller, put that on the alternator.
Demon_Mustang is offline  
Old 04-08-2005, 02:10 PM
  #3  
Djs94stang
3rd Gear Member
Thread Starter
 
Join Date: Feb 2005
Location:
Posts: 542
Default RE: Feedback on underdrives

I have a 94...it may be different than the 86 to 93's. My stock alt pulley was 2 inch and the one that came with the kit was 2-1/2 or 2-3/4 inch. Anyway...you answered my question...I'm going back to the stock (smaller) pulley. I think other than the crank the water pump pulley is more important....thanks.
Djs94stang is offline  
Old 04-08-2005, 07:13 PM
  #4  
Demon_Mustang
3rd Gear Member
 
Join Date: Sep 2004
Location:
Posts: 837
Default RE: Feedback on underdrives

Yah, you should always stay with whatever is the smallest for the alternator, hell, you should even go buy yourself an overdrive pulley for the alternator to compensate. But I guess see how the stock one goes, and if it's still really low, then look into an overdrive.
Demon_Mustang is offline  
Old 04-09-2005, 12:14 PM
  #5  
Djs94stang
3rd Gear Member
Thread Starter
 
Join Date: Feb 2005
Location:
Posts: 542
Default RE: Feedback on underdrives

I switched back to the 2 inch for the alt. It's much better. I put a digital vm on it and it will drop below 12.5 volts when it is idling, with the fan on the 2nd speed, headlights on, rr def on. With the 2-1/2 pulley it would drop considerably at idle with just my foot on the brake peddle. Thanks for the tip about the overdrive pulley, Demon...I didn't know they could be purchased. I suppose if I find a problem with it now I could go down to a 1-3/4 if they make one.
Djs94stang is offline  
Old 04-09-2005, 12:46 PM
  #6  
vfast
I ♥ Acer
 
Join Date: Jul 2003
Location:
Posts: 11,394
Default RE: Feedback on underdrives

this is why I always ungrade my alt when doing this mod
vfast is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
mapitts
5.0L GT S550 Tech
49
05-15-2016 02:57 AM
Matt's 95 Stang
5.0L (1979-1995) Mustang
2
10-05-2015 07:16 AM
GimpyHSHS
4.6L (1996-2004 Modular) Mustang
3
09-18-2015 12:27 PM
2015Ecoboost
New Member Area
3
09-17-2015 01:48 PM
TfcCDR
V6 (1994-2004) Mustangs
1
09-14-2015 12:08 PM


Thread Tools
Search this Thread
Quick Reply: Feedback on underdrives


Advertising
Featured Sponsors
Vendor Directory

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.