[Old Goat 67]

Here is the explanation I sent to cardone earlier.

Maybe it will help you to understand better.

The pumps you are putting out mostly have the impellers configured like this.

Improper or no contour to match what the plates have.


Which, when placed in the timing cover on the front of our Pontiac engines leaves a gap between the impeller and plate like this which causes cavitation and drastically reduced & improper water flow through the radiator. This gap generally measures ¼” or more.



I was lucky enough back in 2008 to find one of your 58-299 pumps that got through your system without having had the OEM type impeller cut down which looked like this. Here is a shot of the one I bought by chance and how it fits.

Mine runs so cool it's like I FINALLY have a brand new car! The volume of water movement is phenomenal! Engine temperature WILL NOT get above 5° of rating of thermostat! Even with AC on in July in Louisiana.



Notice how well the taller/contoured vanes pump fits the original plates here. Curvature of the blades is an exact match to the original plate.

The bulge in the plates was actually part of the pump chamber, allowing maximum pump volume for the given space allowed in the front of the timing chain cover.



This gives you a better idea where these pumps, plates and timing chain cover go together.



Inline Tube has started making the OEM correct plates, but NO ONE is putting out pumps that match.




This eight bolt pump configuration was used from 1963 to 1968 and then an eleven bolt pump was introduced that went all the way to 1979 when Pontiac stopped producing the V8 engine.

The eleven bolt pumps have the same problem as these I just discussed.


We are constantly being asked by all the other Pontiac restorers where to get a PROPER water pump and we have to tell them “No one builds one”.

I’m sure we would be able to make it worth your while if you were to correct this grievous wrong we have to live with.

I would be willing to bet we could sell 500 to 1000 of these in the first month they became available.

Does that help?

Charles