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  • Fox 5.0 Mustang Tech

how to tell if you have underdrive pulleys or not

  • Thread starter Thread starter stang2841
  • Start date Start date Sep 25, 2004
S

stang2841

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Jun 12, 2004
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palm harbor florida
Sep 25, 2004
#1
  • Sep 25, 2004
  • #1
Well I want to be able to tell if I have underdrive pulleys on my car or not, I found out the other day that my timings been advanced arready and theres a few mods on there arready and I was wondering if the previous owner arready covered it or not.


When I get a chance Ill post pics of all that but can anybody tell me off the top of there head what are some noticeable things.


Also would like to remove smog pump and do pulleys at the same time, anybody have a diagram or a page of what is needed to do both of them?
 

PhLoBuS

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Aug 15, 2004
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Beverly, MA
Sep 25, 2004
#2
  • Sep 25, 2004
  • #2
the pulleys are different sizes if they are aftermarket pulleys hmm I will have to get back to you on that
 

1qckFOX

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Sep 25, 2004
#3
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Mine are blue? lol
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Sep 25, 2004
#4
  • Sep 25, 2004
  • #4
if you are not having charging or temp issues (sometimes a tell tale sign), i might find a bud with stock pulleys and compare. or measure yours and go to the parts store and ask to see a replacement stock pulley - compare the dimensions.

good luck.
 

Rick 91GT

Mustang Master
Nov 29, 1999
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Sep 25, 2004
#5
  • Sep 25, 2004
  • #5
What is the approximent diameter of the water pump and crank pullies....

If the crank pulley is around 5" it is stock, most aftermarket underdrives are around 2.75".

The water pump pulley is really a OVERDRIVE with the underdrive pulley set, it will be around 5.25" in diameter.
 
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NightStalkersSO

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Gilbert, Az
Sep 25, 2004
#6
  • Sep 25, 2004
  • #6
ummm, most stock pullies have little ford ovals and part numbers on them. Aftermarket isn't going to have that
 
M

Mark89Notch

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Long Island,NY
Sep 25, 2004
#7
  • Sep 25, 2004
  • #7
A/C question

I have underdrive pullies. When I stop at a light the A/C doesnt work to well. Is there a fix besides changing all the pullies back to stock?
 

Rick 91GT

Mustang Master
Nov 29, 1999
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Sep 25, 2004
#8
  • Sep 25, 2004
  • #8
The A/C should not be effected that much, I would bet it is the amp your alt is putting out sinmce it will drop severely at idle with underdrives, or the A/C could be getting low on freon.
 

Gearbanger 101

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#9
  • Sep 25, 2004
  • #9
Mark89Notch said:
I have underdrive pullies. When I stop at a light the A/C doesnt work to well. Is there a fix besides changing all the pullies back to stock?
Click to expand...
You could always bring up your idle a tad.
 

Michael Yount

Mustang Master
Apr 10, 2002
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Charlotte, NC
Sep 25, 2004
#10
  • Sep 25, 2004
  • #10
The a/c can definitely be affected by underdrives. Not only is the compressor turning 20-25% slower than it was before, the fan is also usually turning a bit slower as well, pulling less air across the condenser coil - which impacts a/c output at idle.
 
M

Mark89Notch

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Long Island,NY
Sep 25, 2004
#11
  • Sep 25, 2004
  • #11
Im moving to Florida so ill have to get some stock pullies. The cold A/C is worth more than the hp.
Would an electric fan help?
 
S

stang2841

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palm harbor florida
Sep 25, 2004
#12
  • Sep 25, 2004
  • #12
hm, If I take pictures can you guys verify for me or not?
 
N

NightStalkersSO

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#13
  • Sep 25, 2004
  • #13
If you take good close ones, yeah
 

blkstangman88

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Sep 26, 2004
#14
  • Sep 26, 2004
  • #14
look at the crank pully, or feel it, my stock crank pull have regulay hexigon bolts and my under drive pullys came with big allen wrench bolts, just a thought.
 

Rick 91GT

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Nov 29, 1999
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Sep 26, 2004
#15
  • Sep 26, 2004
  • #15
Michael Yount said:
The a/c can definitely be affected by underdrives. Not only is the compressor turning 20-25% slower than it was before, the fan is also usually turning a bit slower as well, pulling less air across the condenser coil - which impacts a/c output at idle.
Click to expand...

Very true they are about 25% less then stock. When I first got underdrives my motor was stock A/C and all, only issue I ever had at idle where it was notciable difference was a weak alt and a bad clutch fan that wasn't working properly cooling the rad and condenser.

MARK89NOTCH- The stock fan assembly and fan clutch is the best cooling set-up out, they do a better job then most electrics as long as they are in good working order.


Micheal do you have nay pics of the 5.0 in the volvo, I've seen you post any but I want to show some people. Rick91GT@suscom.net
 
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