6 bolt oil pump housing vs 7 bolt oil pump housing

[brandonf90]

can anyone tell me the difference between 7 bolt and 6 both oil pump housings and show me a picture of the difference?? it would be much appreciated

 

[19Eclipse90]

Bolt patterns are different, the 7-bolt is curved at the oil pan flange where the 6-bolt is flat. See / Read : 6 bolt oil pump on 7 bolt block?

 

[iceguru1114]

Everything you could want to know about the 6 vs. 7 bolt:

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In short, aside from the housing shape difference, certain pumps have helical gears and others are straight cut. I've seen both flavors of gears irrespective of 6 vs. 7 bolt.