Tom,I have not the foggiest idea..The bypass hole in the pump is very small.therefor I believe there is a correlation between the volume pumped and the amount or volume bypassed..I was concerned as to the greater volume of the modded pump vs the bypas volume..so I increased the bypass volume as well..I felt this prudent as Im sure it will bypass a greater volume earlier on..
The actual flow area out of the gerotor thru the pump untill it enters the block is pathetic..Probably no more than 8 to 10 mm in diameter.I looked at this and thought what a waste to have increased the pumping volume when you have this massive restriction going to the block.I dony mind the restriction further up the line,but heck,give it a chance to at least make it out of the pump freely..I put a 14mm reamer down there to open things up a bit..
For those of you with 4 cyl motors,the one thing the std oil pump on a 4 cyl does,is trap air in the bypass channel..It will also at times pick up air and this is bad for the bearings,even momentary..I would open the ally plug up that Alfa so nicely sealed a drilled port off with in the pump.This then bypasses the air and oil directly back to the sump.Make sure though that you open the pump up and fit a 8mm(
-if I remember correctly)Plug to the std internal bypass passage..I know this is nit picking,but it stopped a bearing problem on my littl turbo..
Of course you could go dry sump,uh Ben??
The actual flow area out of the gerotor thru the pump untill it enters the block is pathetic..Probably no more than 8 to 10 mm in diameter.I looked at this and thought what a waste to have increased the pumping volume when you have this massive restriction going to the block.I dony mind the restriction further up the line,but heck,give it a chance to at least make it out of the pump freely..I put a 14mm reamer down there to open things up a bit..
For those of you with 4 cyl motors,the one thing the std oil pump on a 4 cyl does,is trap air in the bypass channel..It will also at times pick up air and this is bad for the bearings,even momentary..I would open the ally plug up that Alfa so nicely sealed a drilled port off with in the pump.This then bypasses the air and oil directly back to the sump.Make sure though that you open the pump up and fit a 8mm(
-if I remember correctly)Plug to the std internal bypass passage..I know this is nit picking,but it stopped a bearing problem on my littl turbo..Of course you could go dry sump,uh Ben??
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la_strega_nera
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