I was always under the impression that the A/C pumps had less fins on the impeller specifically to move coolant slower so it would pick up more heat while in the motor. By product of that was less cavitaion.

Summit used to sell the sheet metal plates to put on the back of impellers too. They were a couple bucks.

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Official Cookie and Mater Tormentor.

The water pumps for LA engines with AC had fewer vanes, but the water pump pulley was also smaller so the pump and fan were driven faster.

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Joshua

I think I would be cutting vanes off the water pump, or reducing their area, if anything.

Lou

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Home of Slant6-powered fun machines since 1988

I have a tangential question to ask: what are the track regulations on what you're allowed to run in the cooling system? Do they make you run plain water in case you spring a leak so you don't glycol-down the track and make it slick for everyone else?

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

NHRA rules dictate plain water. That said I have never heard of a track, running a "local" meet, checking a street driver. I have had my race car checked, however.

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Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

Yeah, the glycol's a pain to clean up, and it's excellent at countering the VHT. The track crews hate it.
I run glycol cut water in my HAMBster between meets, but change it out for race day. Keeps the rust down.

Doc, do you know the manufacturer of the pump in your picture that you cut half the vanes off? I see it's blade bend direction's "cupped" favoring the direction of rotation, and would be more efficient than those bent the other way. That one'd likely not need a capture plate on the backside.

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I think you can add 'water wetter' to the plain water at the track.......

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

Yep, lots of folks do that. I know several non-radiatored cars that run it.
I tried it but it still rusted up more than I like, in spite of the claims.
Race days on plain water and back to mix works for me (I re-use the mix, I'm cheap ).

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Dick, 225% crazy.
Hobby (cars, that is) Photos link

Sorry to say that I do not know the brand of pump that is... it's just one I pulled out of the "used waterpump" box.
DD

No sweat, just thought it might've helped the original poster.

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Sex, drags, and rock & roll.
Dick, 225% crazy.
Hobby (cars, that is) Photos link

Anti-freeze is only against the rules in Pro and S/Pro.

RT 66 checks.

Indy checks.

41 only checks your cash.

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Official Cookie and Mater Tormentor.

I run mostly small nostalgia meets, and mostly at Famoso. They ask us to do it voluntarily, and they don't check. However if you Glycol the strip you will be invited to leave, by both the track crew and other racers. Pretty much the same at Fontana and up at Eagle Field.

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Sex, drags, and rock & roll.
Dick, 225% crazy.
Hobby (cars, that is) Photos link

Thanks for the reminder! Better dump the glycol for MATS. They are rabbid about it at Las Vegas.

CJ

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Part of Tyrde-Browne Racing