Engine Short vs. Long Water Pump


Founding Member
Feb 13, 2002
Was doing a little work belt work/maintenance on my 2002 and realized that I have a long (87mm) water pump. Many sites state that Ford changed in 2001 to the short (65mm) style:
American Muscle: Your Mustang's Cooling System and How to Improve Efficiency (see section 2001 Mustangs: How to Identify the Water Pump Pulley)

I've seen threads and sites where 2002's that were similar to mine and had long style pumps, does not seem like Ford cut the change in cleanly.

Mustang Boards: Wrong Water pump pulley for 02
Mustang Forums: Guy had a short on a 2000

I am not surprised, as I know that on my 2002 I had to order an older thermostat as the housing fits an RT1234 not the RT1110 (too tall) that is called out by some parts sites. FordParts.com has the RT1234 as build dates from 9/18/2000-8/5/2002.

So basically I have two questions:
1) Aside from requiring a different pulley, are the long and short water pumps functionally equivalent? That seems to be what I read here and other other boards/vendors.
Stangnet: Will a 00' GT water pump pulley fit my 02'?

2) Is there any reason (performance, fitment, quality, longevity) to choose one over the other? i.e., if I change my water pump should I go to a short one instead?

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