a thread on the Melling oil pumps.
The "Select" pumps are recommended by Melling for use in solid motor mount and/or high performance apps, whatever that's supposed to mean. To be safe, use the Select line.
Melling supplies their castings to others, so the problem is not just Melling-branded pumps. Other pumps to watch out for:
Sealed Power 224-4143
The sheet below is what's supplied w/the standard-type pumps: