waterpump interchange

ganzey:

There is a difference in the length of the snout of the water pump: it is either short or long. The pump, long or short snout, is the same in terms of fitting into the block recess. The u/d pulley will be deep or shallow to fit the long or short snout, respectively. I do not know if the difference in length is because of a NPI and PI engine difference or if it is a difference between the Romeo and Windsor engines. In any case, you need a shallow pulley for the water pump.

Instead of buying a new pump, you can have the water pump pulley milled at a machine shop or you can call Steeda or March or ASP and ask if they will sell you a shallow pulley for a short-snout water pump. You can run the stock water pump pulley and get most of the benefit of the underdrive crank pulley size. Just check belt length because you may need a little longer belt. If the tensioner is not at the limit then the belt is OK.

HTH,

Chris