Let me preface this post with the statement that I am certainly not getting anything out of this and it is strictly an FYI for all of my fellow L owners.

Turns out this bad boy is the same water pump used in all 4V Mustangs (part number YR3Z-8501-AB or the Motorcraft number is PW402). Just ordered one from Gary at Fordpartsonline for $75 plus shipping. I certainly don't want to screw any tuners since without them we wouldn't be having the fun we are but $30 is $30.

 

Really!?

I thought that the housing was the same, but the 'R' had a different impeller design.

-Kris

 

Nope...same water pump.

Check out this thread:

https://www.f150online.com/forums/sh...ht=cobra+water

Take care,

Dan

 

I heard the same thing, impeller in the "r" pump moved a heavier volume of coolant. ......just what I heard.

 

Actually the pumps are not the same. I was mistaken back then, because I had been told they were the same. But the R pump does have a disc on the impeller to help flow. You can use the regular 4V pump, it's frees up power just as good, but the R pump moves more coolant, that's why we've switched to selling it now that we know it's different.

 

Dohhh!!! Darn you Sal! I had actually based my purchase on the part number from a previous post and the post referenced above...my bad.

Dan

 

Hey Sal, so are you saying we could use the extra flow of the "R", or is the stock 4V pump adequate? Is the power figure the same? Thanks, Jack

 

more flow = cooler temps = more power

 

What is the part # for the Cobra R pump?

 

The slower the flow=more power IF the thermostat is regulating temp properly. The thermostat will be doing its job if it maintains the temp, no matter what the flow.

 

Then why doesn't the Cobra R use the regular Cobra water pump?

 

if you convert to the cobra r pump, you have to go to the electric fan. Most of these kits use a 160 or 170 degree thermostat I believe. What is the stock temp set?

 

The R may run a higher temp thermostat and need more flow.

 

tallimeca,

The stock thermostat is rated at 180-degrees.

Dan

 

Very true, Frank..in fact in many cases to much flow can increase engine temps.