i am sticking with a stock oil pump from my A15. Hope it is sufficient. i cant find its pumpage volume in any of my 1200 manuals.
An override switch is a good idea I know just the place for it too. cheers
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edit:
oil cooler is in! just piped it all up tonight. I had a temperature sender for a guage put into the sandwich adapter, so it reads engine oil temp straight out of the engine. The piping you see in this picture was not the piping I used. I ended up getting huge 16mm bits and changing it all to 16mm pipe. Good strong 300psi pipe, very rigid, but surprisingly it bent into place easily. Initially, the empty oil cooler filled up very quickly (only idle'd about 15seconds before i could feel hot oil flowing into the oil cooler for the 1st time), a good demo of the old A series stock oil pump! still retaining 10-30psi idle and 40-60 above 3000rpms. The oil temperature took a while to warm up but stayed steadily coming out of the motor at 80-90 celcius while highway driving, and 60-80 while city driving.. all with my 4 speed gbox. (3500-4000rpm highway driving)