The only NEW pin drive S pump availabe seems to be the MiniSpares Sureflo one.
There have been some problems on race Minis with the shaft in these pumps breaking the `ears' off the slot, as the shaft material is really soft. TOO soft....
If you are running these pumps (as I still am) don't thrash it when the oil is cold. That extra oil pressure doesn't help...............
Years ago, all the pump rotors were keyed onto the shaft and yes it was possible to swap shafts, eg put a wide lobe S pump into a 998 by fitting the shorter 998 shaft.
These days the rotor seems to be swaged on, or a press fit, so the old idea is no go.
My new 1412 stroker is getting an RE13 cam (S pin drive shaft) but I'll convert it to take a slot drive pump.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.
