water pump for my 73, which one?

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May 21, 2017 | 11:03 PM

jr73

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Drifting

Joined: Apr 2013

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From: Central Wisconsin

water pump for my 73, which one?

Need help selecting a water pump for my 383 crate motor.
Its a late 90's block, Vortec roller motor originally which I got from Summit done by ATK.
My question is do I buy a pump for the late 90's block with those funky heater hose nipples coming off it? or an older style for a mid 70's block? What about pump rotation?
I'm gonna use electric fans so I don't care about fan issues.
block casting number is 10243880

May 22, 2017 | 01:04 PM

Peterbuilt

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From: mount holly NC

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May 22, 2017 | 10:15 PM

jr73

Thread Starter

Drifting

Joined: Apr 2013

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From: Central Wisconsin

So any long Chevy pump will work?
(compatible with my crate motor?)

Last edited by jr73; May 22, 2017 at 11:00 PM.

May 23, 2017 | 05:09 AM

GUSTO14

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Joined: Sep 2003

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From: eastern NC

Quote:

Originally Posted by jr73

So any long Chevy pump will work?
(compatible with my crate motor?)

The long pump was never used on the Corvette.

What drive system are you using? The '73 belts and pulleys? Or a '90's serpentine system?

Good luck... GUSTO

May 23, 2017 | 07:07 AM

Dynra Rockets

Burning Brakes

Joined: Oct 2012

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I'm sure this has been discussed a million times in this forum but here is what I have in my notes:

Long pump is 6.932"
Up to '70 short std duty, length = 5.625", 5/8" shaft
Up to '70 short heavy duty, length = 5.625", 3/4" shaft
71-82 "corvette length" = 5.8125", 3/4" shaft

I purchased an aluminum short pump for my '69 SB and when it arrived it was about an 1/8" shorter than the original '68 dated pump that came in the car. Some how my 69 got a 70 style pump? I just used a cheap 1/8" aluminum pulley spacer to get the belts back in alignment.

May 23, 2017 | 07:36 AM

jim2527

Race Director

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From: Tampa, Florida

Pump rotation....

Regardless of traditional V belt or serpentine drive, water flows through a Gen 1 small block in the same direction. Serpentine belt runs on the opposite side of the water pump thus spinning it in the wrong direction. This requires a water pump with reversed vanes aka a 'reverse flow' water pump....water still flows through engine in the proper direction.

V belts standard short water pump
Serpentine long 'reverse flow' water pump

May 23, 2017 | 09:55 PM

jr73

Thread Starter

Drifting

Joined: Apr 2013

Posts: 1,747

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From: Central Wisconsin

I want to use the standard 73 drive system. I am making this up as I go along since I bought this car mostly stripped down and don't have most of what I need. The motor I'm swapping in is a 1998 Vortec roller motor and I'm trying to fit as many of the 73 components as will fit on it. When I searched for 1998 pumps it listed it as a counterclockwise pump, I figured out after thinking about it a while that it was because of the serpentine system. My 73 pump bolts right on I just want to make sure it will work on a motor 25 years newer.
I like this Stewart pump but the one for the 73 block has this fitting on top which my old pump doesn't have.

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