Oil Filter Bypass block-off???

[Zerrari GTO]

I just got my short block back from being assem/balanced and the machinists blocked off the oil filter bypass hole with a threaded plug. He said this was to keep the oil pressure up and was a common practice when they built engines. After seeing it, a couple mechanic buddies warned not to use a high pressure or high volume oil pump with this modification or I could blow the oil filter.

Here are a couple pics so you can see:

Are you guys (Grumpy) familiar with this mod and would you recommend it for a street car? What suggestions do you have for an oil pump?

Thanks.

[steal my nametag]

i can't say i would recomend leaving it sealed if you plan on using a high volume pump, as for it bieng "common practice" i've never once seen a street car with it =/

[naviathan]

That's a new one on me. Never heard of it being done at all.

[lbhsbZ]

Its pretty common with performance engines. Jegs, Speedway, Summit, and all the other speed shops sell a little plug to replace the bypass valve, and also sell a different oil filter adaptor w/o the bypass valve.

[steal my nametag]

really i never knew that one.. i knew guys who would get scrap bypass valves and just weld them shut, never knew they sold a part for it... i guess that's what happens when you don't look eh?

[that240guy]

Looks to me like a band aid for a poorly built engine that can't keep oil pressure up.

[pparaska]

The purpose is to keep the bypass from opening and passing unfiltered oil into the oil passages. The bypass is there to keep a plugged filter from blocking pressure (and volume) of oil to the oil passages. The OEs need to do this to keep losers that never change the oil filter from ruining the engines.

 

It's fine to plug it, IMO, if you change the oil filter regularly. I even recommend it in those situations. It has nothing to do with creating higher oil pressure on an engine with a non-plugged filter. The only way it would increase oil pressure to the engine is if the filter is clogged/plugged.

[Turbo Meister]

It has nothing to do with creating higher oil pressure on an engine with a non-plugged filter.

 

I agree with Pete. My 383 had this modification for the last 6 years. This is extra insurance that all of my oil is filtered all of the time.

[Zerrari GTO]

Thanks guys.

 

After Pete's explanation I now understand why the machinists said it would not be a problem to run a high pressure oil pump. After the post by lbhsbz I checked out the after-market performance websites and just like he said, there are plenty of them out there.

[pparaska]

I might add that when the oil is cold, a cheap oil filter might burst since the bypass is blocked. Cold oil can really increase the oil pressure. So the bypass can save you if you start the engine with really cold oil and then rev the piss out of it. Bypassing dirty oil is probably better than blowing up a weak filter case and making a huge mess and possibly ruining the bearings with zero oil pressure. I suppose you could damage the distributor drive gear too, or twist the oil pump drive shaft or mess up the oil pump with the heavy loading when pushing that much oil pressure through the engine.

 

My buddy across the street with a 427 Cobra replica just replaced his oil cooler. He said the repo oil cooler came with documentation that said something like "we sell a bypass filter/hose kit for those people that insist on stomping the gas pedal with a cold engine - the oil cooler can not take the pressure."

[Pop N Wood]

I am not sure how much good this mod is going to do you since most spin on oil filters contain an internal bypass anyway

 

http://minimopar.knizefamily.net/oilfilterstudy.html#m1-301