I am about to do a oil bypass mod on my 7r mag cases.
I have the info on what to do,but the one hole needs blocking,either with a threaded plug or weld up? Which would be best,or how has it been done?
Also there is a smaller hole below the big hole that needs plugging,does this smaller hole also need plugging or left alone.All the info i have so far does not show or mention the second hole thats about 5mm in diameter.
Any help would be welcome.
oil bypass mod
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Alan @ CanfordClassics
- Nurse, I think I need some assistance
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In fact Mike is doing this as we speak on a pair of my 2.2S cases. Give him a call.
Alan
Alan
http://www.canfordclassics.co.uk
Porsche Restoration & Sales
Porsche Restoration & Sales
By-pass Mod
Hi it is not that hard to do this mod leave the 5mm hole as is,tap (1/4 NPT) and screw in a plug, I always wire this for extra security. To drill the new bypass hole I made up a guide to make it easier Regards Peter
1973 911S,1965 http://www.youtube.com/watch?v=O56Y0j518Bc
By-pass Mod
Hi Paul as far as I know it helps with returning the oil to a liquid from a aerated mist, also stops the oil in the bottom from frothing and reducing HP just how much 
.All the motors I have worked on have them fitted as orig item Does yours Regards Peter
.All the motors I have worked on have them fitted as orig item Does yours Regards Peter1973 911S,1965 http://www.youtube.com/watch?v=O56Y0j518Bc
I have never seen this before,but there again i have not had many early 911 bottom ends apart.
I would of thought this was not required with a dry sump,and now the oil bypass which also helps reduce the level of oil in the sump.
May be its something porsche came up with for hot climates etc
I am sure some body will chirp in who knows
I would of thought this was not required with a dry sump,and now the oil bypass which also helps reduce the level of oil in the sump.
May be its something porsche came up with for hot climates etc
I am sure some body will chirp in who knows
Hi
The gauze in the bottom of the crank case is usually removed when rebuilding the case, also the oil bypass mod will not necessarily reduce the oil level in the bottom of the crank case. Originally when the pressure relief piston opens it dumped the excess oil into the crankcase for the scavenge pump to pick up and put into the oil tank, with the mod it blanks the outlet to the crankcase and routes the excess oil down the newly milled hole that goes to the suction side of the pressure pump this saves the pump from doing as much work. When doing this mod remember to install the correct springs and pistons as they are different to the original ones.
Hope that helps.
Kind Regards
The gauze in the bottom of the crank case is usually removed when rebuilding the case, also the oil bypass mod will not necessarily reduce the oil level in the bottom of the crank case. Originally when the pressure relief piston opens it dumped the excess oil into the crankcase for the scavenge pump to pick up and put into the oil tank, with the mod it blanks the outlet to the crankcase and routes the excess oil down the newly milled hole that goes to the suction side of the pressure pump this saves the pump from doing as much work. When doing this mod remember to install the correct springs and pistons as they are different to the original ones.
Hope that helps.
Kind Regards
John
1970 2.2E Coupe.
2004 996 GT3 mkII
2015 Skoda Octavia VRS TSI DSG.
2021 Toyota GR Yaris Circuit Pack
1970 2.2E Coupe.
2004 996 GT3 mkII
2015 Skoda Octavia VRS TSI DSG.
2021 Toyota GR Yaris Circuit Pack
