Just converted my 84 351w from v belt to serpentine , VIA junk yard pullies. it is a two belt system (1 BELT FOR THE A/C ONLY)
Actually two questions:
Do I need a Revere flow water pump? AND If i do need one, what year , model 351w water pump do I need to purchase I think my 351w came from a galaxy, if that helps.

 

First, let's start with proper terminology, for the sake of eliminating confusion. It's not a reverse flow water pump, it's a reverse rotation water pump. The impeller vanes are angled differently to move the water through the engine while spinning in the reverse of standard. It still moves water from the radiator to, and through the engine.

Second, whether or not you need a reverse rotation water pump with your belt conversion will depend on if your donor engine had one. Which way does the belt wrap around the pump pulley? If it wraps opposite of the crank, then yes, you need a reverse rotation pump. You need to get one that fits the engine your serpentine set-up came from, if you want to be sure you have the correct part. Why didn't you just take the water pump when you took the pulleys and brackets?

 

I am stupid but, I did nit realize there was that I might need the old worn out pump

 

It's not just the water pump. The ports in the timing cover are angled differently to accomodate to reverse rotation pump also.

 

It gets a little complicated, doesn't it?

 

The 302's used the same timing cover with both rotation water pumps until sometime in the '90's.

 

The reverse rotation timing covers went back well into the 80's. I looked it up and some reverse rotation pumps were used on the standard rotation covers and some weren't. There were a few different reverse rotation pump part numbers. The important thing is that the two parts match. The pumps designed for the reverse rotation timing cover won't seal up at all on the standard rotation cover. Not even close.