289 hipo water pump impeller

[jk66gt350]

I know the 289 hipos had a 6 vane impeller vs the standard 8 vane - supposedly to reduce cavitation at high rpms from some info I've read.  Are there other advantages of using the hipo impeller?  For normal street use with only occasional high rpm blasts, if you are not concerned with being "correct", are you better off running a standard impeller vs hipo for good cooling?  I've done some searches and cannot find any info on when you might be better off with one vs the other.   

[pbf777]

For normal street use with only occasional high rpm blasts, if you are not concerned with being "correct", are you better off running a standard impeller vs hipo for good cooling?

     For the manor in which most of the restored "show cars" and how they are most often utilized, that being when not just idling or low-speed operation in parking lots, but also with "kid-glove" treatment when out on the road, then yes, you'd be better off with the standard pump impeller.   

     Scott.

[Bob Gaines]

For normal street use with only occasional high rpm blasts, if you are not concerned with being "correct", are you better off running a standard impeller vs hipo for good cooling?

     For the manor in which most of the restored "show cars" and how they are most often utilized, that being when not just idling or low-speed operation in parking lots, but also with "kid-glove" treatment when out on the road, then yes, you'd be better off with the standard pump impeller.   

     Scott.

+1

[jk66gt350]

OK, thanks for the replies.  Never thought about it before and not even sure which is in my water pump.  A friend with a K code in his hot rod recently said that he was told by his engine builder when he rebuilt his 289 about 10 years ago, that he would be better off with a standard impeller vs hipo for "normal" use.  If I ever have to repair my water pump, I'll keep that in mind. 

[427heaven]

They both work just fine for normal driving, with some performance driving thrown in for some excitement, whatever that means. The benefit from running the standard pump from the Hipo pump is it will keep an additional 300-500 dollars in your wallet if that sort of thing matters.

[roddster]

 +1, I used to have the regular water pump in my 67 GT 350 for years, no issues.  When it leaked I had Shelby Parts & restoration rebuild it with the more correct impeller. Works fine too.  No temperature issues either way.

[Dan Case]

From personal experience with a single car over four decades:

I have used a standard pump and I have used a pump with HP289 specific impeller. This is in an original Cobra where the radiator is a long way from the grille.

At 630 average feet above sea level.

With the standard pump impeller:

Overheating in slow stop and go traffic was not an issue unless the ambient temperature got above about 95°F.

Oveheating (up to indicated 240°F) during high speed open track play was a serious problem when above about 5,000 rpm very long.


With the HP289 impeller:
Overheating in slow stop and go traffic had to be watched when the ambient temperature was over about 75°F. The first traffic light stop was okay, the second was hotter, and by a third I was looking for a place to get a cool down run above 40 mph.

Overheating was not a problem running at red line on a road coarse even when the ambient was higher than I was comfortable in. (It is always hot in a Cobra's cockpit unless it is cold weather.)

And then we moved to 5,400 feet above sea level. At that altitude it is very common to find large electric after market fans added to any kind of old car or truck deal with the low air density and attendant lower heat transfer capacity. We added the largest highest flow electric fan the car's electrical system could deal with to prevent overheating driving to Lowe's and back with a HP289 impeller.

My recommendations to original Cobra and HP289 car owners are to install a standard pump for all uses except for high speed touring through a desert or serious open track play. If the car is mostly used as a road track car, install a HP289 or Boss 302 impeller.

Bear in mind that no one was selling collector cars in the 1960s. If they sold a high performance Ford, Ford expected owners to run to red line frequently and some would go racing.

[Bigfoot]

^^
Smart