Big block oil pump ??????

Posted this a long time ago,nobody knew,still trying to figure it out.Bottom picture on right is stock pump.

What's the question?

Looks like a high volume pump to me.

There are interesting marks in the 7-9 o'clock areas on the second picture from top. If the impeller rotates clockwise in that picture, the marks are probably cavitation.

R.

Stock pumps have the elongated hole put given the passage from the block is round its questionable as to the benefit. Smoothing the rough casting in all those ports is a definite bonus.

I imagine the slotted rotor is someone's idea for lubrication. How many millions of pumps are out there without the slot ?!?!? Pointless.

If it someones idea and pointless,then Chrysler is the culprit,that is a N.O.S. pump in the original box unopened when I got it 30 yrs ago !!

I think everything has a reason (good or bad!). it may have been a slot to secure it for machining somewhere down the line but if that is the case you'd sure think all of em would have it (or something similar).

Well they haven't made them like that since so obviously they saw no point in it either !!!

Just won't quit will you,as far as since,maybe just because you have never seen one thats an assumption on your part and you know what that can mean !!

Also if you want to turn a simple question into a p#####g match,no better place than Moparts !

Still not sure what it is you wanted to know, since you didn't post a question that I could see.

The question was the purpose of the slot in the outer rotor!

They are built like that to start arguments. See how good it worked!

Amen to that !!!

Bill all the Melling pumps I have gotten in the last decade plus have at oval hole

Bill