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Belt Length

  • Thread starter Thread starter JD1964
  • Start date Start date Aug 14, 2013

JD1964

there is enough sticking out to grab on to
15 Year Member
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Aug 14, 2013
#1
  • Aug 14, 2013
  • #1
I'm going to remove the smog pump eventually. I'll be keeping the factory AC (still blows nice and cold). I've been reading and understand I'll need an 84.5" belt after the smog pump is removed.

To expand, under-drive pulleys might be in the mix too. Will that affect the belt length? I see the vendors offering them and they don't mention the need for a different belt. I figure that since the crank pulley is smaller, and the alt and water pump pulleys are larger, the belt length from a typical pulley swap basically stays the same?

Is this correct?
 

newskool

Active Member
Oct 17, 2006
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Aug 15, 2013
#2
  • Aug 15, 2013
  • #2
The best thing you can d is measure it with a string. Run it around the pulleys like you would the belt then measure it.Take tha measurement to the parts store of your choice and voila you will have the correct belt length.
 

RsStanG1987

I shaved all my pubes playing this game.
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Aug 15, 2013
#3
  • Aug 15, 2013
  • #3
The only pulley smaller than stock is the crank.. The 84.5 will work
 

84Ttop

They make new pistons every day, so why worry?
5 Year Member
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Aug 15, 2013
#4
  • Aug 15, 2013
  • #4
Leave your stock pulleys alone, in my opinion. I was never a fan of underdrive pulleys. Something about spinning all of your accessories slower just doesn't sit well with me...
 

mikestang63

SN Certified Technician
Aug 27, 2012
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Aug 15, 2013
#5
  • Aug 15, 2013
  • #5
I have used U/D pulleys on several cars and they work fine. The key is you must have a 130 amp 3G alternator and your cooling system needs to be in good working order. Also, do not use a race crank pulley. You should use the same length belt but I would check with the pulley vendor. Stay away from the cheap off brand sets as their quality and tolerances are questionable.
 

cevtv

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Sep 15, 2002
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Aug 15, 2013
#6
  • Aug 15, 2013
  • #6
RsStanG1987 said:
The only pulley smaller than stock is the crank.. The 84.5 will work
Click to expand...

Unless he uses one of the kits with an overdrive alternator pulley.....
 

RsStanG1987

I shaved all my pubes playing this game.
10 Year Member
Mar 13, 2004
569
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Aug 15, 2013
#7
  • Aug 15, 2013
  • #7
They all come with a bigger alt pulley bigger water pump pulley and a smaller crank. I've used the same belt with the stick pulleys and the alt pulley
 

cevtv

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#8
  • Aug 15, 2013
  • #8
RsStanG1987 said:
They all come with a bigger alt pulley bigger water pump pulley and a smaller crank. I've used the same belt with the stick pulleys and the alt pulley
Click to expand...

:sigh: No....the March Power & Amp series pulley set has a smaller, overdrive alternator pulley (1 11/16").
 

mikestang63

SN Certified Technician
Aug 27, 2012
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Aug 16, 2013
#9
  • Aug 16, 2013
  • #9
cevtv said:
:sigh: No....the March Power & Amp series pulley set has a smaller, overdrive alternator pulley (1 11/16").
Click to expand...

Correct. I am running that on my car- recommended for automatics- as the stock alt pulley (2 3/8'?) will not spin the alt fast enough to maintain a proper charge. Just go to the vendor's website and it should tell you the appropriate belt. I needed a slightly shorter belt do to the smog pump delete pulley.
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
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Aug 16, 2013
#10
  • Aug 16, 2013
  • #10
Make sure your tensioner is up to snuff as well
 

JD1964

there is enough sticking out to grab on to
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Aug 16, 2013
#11
  • Aug 16, 2013
  • #11
Dayco 5060845 on the way.
 

mikestang63

SN Certified Technician
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Aug 17, 2013
#12
  • Aug 17, 2013
  • #12
John Dirks Jr said:
Dayco 5060845 on the way.
Click to expand...

That's 84.5" which should fit as long as your alt pulley isn't overdrive, but again, best to measure or better yet pull up to the parts store, pop the hood and try out a few belt lengths while you are there.
 

cevtv

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#13
  • Aug 17, 2013
  • #13
I believe I needed an 82.5 with the overdrive alt. 84.5 with regular under drives.
 

Grabbin' Asphalt

10 Year Member
Jun 10, 2013
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Aug 17, 2013
#14
  • Aug 17, 2013
  • #14
cevtv said:
I believe I needed an 82.5 with the overdrive alt. 84.5 with regular under drives.
Click to expand...

Same here, when I got my '95 130amp 3g, it was a little tight. But I HAVE to use the crowbar on the tension pulley to left it up, socket won't slide past the belt for sure.
 

JD1964

there is enough sticking out to grab on to
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Aug 29, 2013
#15
  • Aug 29, 2013
  • #15
My conclusion is such.

The 84.5 worked with the smog pump delete. It also worked when the UD pulleys were installed but the tensioner was sprung all the way down (completely vertical).

I went a got a 83.5 and it fits perfect with smog pump delete and UD pulley combined.
 
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