Quote: With the HV pump an improved oil pump driveshaft is recommended for the higher load. The hex is hardened, the taper to the hex is radiused and the gear is pinned. Though nor common, the HV pump can fail the standard shaft.
As long as you have the correct shaft the only drawback is you loose one or two HP. I use one on a B engine with full groove bearings and performance clearances. It helps keep the hot oil pressure at idle reasonable with that setup.
I think the stock distributor shaft would be the main problem with the HV pump. Where would be the cheapest place to pick one up ? I just can't figure why the stock shaft won't fit into the stock pump. It fits fine in the HV pump. Everything Looks good. Nothing seems to be nicked or galled. just Very Very tight. Would a light clearance job inside with a small fine file make any sense
Can you do a close inspection of the stock pump? Is there a burr or poorly machined area? I would feel comfortable removing a localized problem with a file or such but wouldn't want to file the whole hex area.
I think I'll try to smooth the inside a bit. The shaft seems to only ride on every other surface. If I can't get the shaft to fit the stock pump, I will most likely use the HV pump for the time being and try and pick up a hardened shaft sometime.
