Undy Dave I pulled apart a stock water pump and the back cover on my Edelbrock. The Stock ford one has the same number of fins on the impellor but there was no plate to help move the flow along. This pump could have been a water pump without AC. The Bearing was bigger on the EDELbrock. I did clean up the casting on the ELEDbrock pump. Alot has to do with the CORRECT pulleys on the waterpump and crank shaft. I went with the march setup and that motor overheated everytime. I got a custom pulley from ASP with the correct size as stock ones. I have not had an over heating problem since. I am also running a larger thermostat than the FE one that is called for. Everybody gets different info again
Rick L