Aluminum vs Castiron water pumps?

[Rhymingmechanic]

I would pick a water pump based on impeller style instead of material. When I shopped around for a Pontiac pump, an iron one ended up having the factory style impeller fins. An aluminum one had the stamped steel impeller typical of a lot of aftermarket pumps.

A quick Google search showed the Flowkooler pump with a disc on the back of the impeller. That's probably meant to increase efficiency vs. an open impeller. (I'm not sure what the stock impeller looks like.)

 

[mpack88]

I'm thinking about getting me into the cast-iron flowkooler. But they do make one aluminum crazy enough the aluminum one is cheaper

 

[super20dan]

long time ford v8 owner from the 70,s. they don't like a 195 deg thermostat. I ran a 170 in mineand even a 160. tried a 195 to get better heat in winter and the trans didn't like it at all. 195 is way to hot for these older engines.

 

[mpack88]

That seems to be common on Clevland engines. I know a 351c had a high flow thermostat from the factory. Not sure why the 400/351m had 195 standard flow.

 

[Silk]

A cast iron waterpump is rebuildable...not that anyone rebuilds waterpumps these days.

 

[MarkM66]

If the temp gets over the rating of the thermostat, a lower rating isn't going to make the engine run cooler.

If you're confident in the radiator, and fan, then add an electric fan for when you have long idle time/stop and go traffic. A puller fan, if there's room.

 

[mpack88]

I would think that to.

 

[circuitsmith]

Couldn't retarded ignition timing contribute to this?
1975 was in the dark days of tuning for emissions.

 

[mpack88]

Its timing was originally 6° btdc it has sense then been adjusted around 16° which is to high. I'm going to bring back down to 12.

 

[Jake_J]

The aluminum water pump will have you some weight but it will also lighten your wallet more than an cast iron one. If you're concerned about overheating I would worry about having the whole cooling system working smoothly before investing in better parts. You don't need to switch your coolant if you change to an aluminum water pump as aluminum doesn't have issues with any of the 3 major types of automotive coolants.

 

[Lubener]

Originally Posted by mpack88
The radiator is a brand new 3 core copper unit. Should be more than capable. I'm going to install gauges in it this weekend to get accurate temps. Also will install oil pressure and voltmeter.

If it has A/C, is the condenser blocking airflow?

 

[mpack88]

Looks good to me. And the ac works fine

 

[mpack88]

I've upgraded many things. Everything in the cooling system is new amd working except the water pump. According to my research Cleveland engine have hot idle problems and a better designed pump should fix it. Well I ordered the flowkooler aluminum pump and well install with a new timing set when I have time. I will repost to show the results better or worse.