Inliners International Forums General Discussion Hi Performance Making 230-250 water pump shorter

This has probably been covered here before but here goes anyway.

I replaced my '70 Nova 2-row radiator with a 3-row, and then found out it left no room for the fan blade. So I needed a shorter water pump. This is how you can do it: Press the pulley flange down further on the shaft and use a small block pulley 69-85 for LONG water pump. I used a single groove pulley.

Do not press against the impeller, use a small socket to put the load against the shaft instead. And a deep well socket to slip over the pulley end of the shaft, 15mm seemed to work well. The shaft will slide into the socket while the socket pushes the flange down.

Once done, cut the shaft down if the tip is in the way. Leave some exposed for centering the pulley.

That is a clever idea.
It has one other advantage - for a big motor, using the late long pulley gives better cooling since it's smaller, but this way it will align with the early belt grooves. I might actually try that, my 292 runs kinda warm with the big 283-style pulley.

The diameters look different but pressed against each other, they are actually almost identical. Can't tell how deep the belt will ride in the groove though. But as far as the speed goes, I'd say it has to be roughly about the same. You really had to put them against each other to believe

Oh yea this is an aftermarket cheap chrome pulley, (Spectre) We sell them so I just grabbed one to see how close it would fit, and ended up buying it. Just need to wax the heck out of it so it won't rust.

As most people here know, there are 2 different diameters of water pump pulleys used and 2 different belt spacings used. The stock pulley shown in the picture is the smaller diameter of the 2. I put a large diameter water pump pulley on my car to slow down the fan and pump. The Crome pulley shown is used on sbc with a/c. There is also a bigger sbc water pump pulley that could maybe be used in the same way. On my nova the power steering belt is closest to the front of the car. Would there be room for the p/s belt to just run between the crank pulley and the p/s pump? It might clear the new water pump pulley but it would be close. The best chance would be if the wide belt spacing balancer and brackets were used. Jay6155