340 cui... different fuel pumps ?

[brasil]

Looking for a new fuel pump for my 340 cui Chally I found different pumps for 70 and 73 cars... why ? I thought the engines are the same .. did I miss something ?
Or is it a question of the timing chain ?? i.e distance between chain and  pumparm ?                               


http://www.rockauto.com/de/cart/


Any ideas ?

Greetings Juergen

[burdar]

The difference is most likely the outlet fitting.(style and/or location)  The fuel pump to carb lines are different and the fuel filter is in a different location.  One pump might have a hose nipple on the outlet end...the other might have a threaded end on it.  The actual pump will fit on a 273, 318, 340 or 360.

[cudabob496]

I'd be equally concerned about a 3/8 diameter opening, or a 5/16 opening.

[burdar]

Both have the same size outlet threaded fitting on them.  Just looking at the pictures on RockAuto you can see that the difference is the location of the threaded outlet.  The outlet is clocked differently because of the different pump to carb lines and filter location.  Compare the outlet fitting orientation on both pumps and you'll see the difference.