Mike_B

Guys, got the picture below from the Scoggin-Dickey catalog. Not that you'd ever want to leave the plug out, but how can it affect oil pressure?

BLOCKMAN

It can't affect oil pressure once the oil filter is full the oil will go the path of least resistance and bypass the filter.

CFI-EFI

Leaving that plug out won't affect oil pressure at all. No plug, no oil pressure! As per "Chevrolet Power".

RACE ON!!!

BLOCKMAN

Hate to inform you but don't believe all you read, After 27 years of building performance engines we have ahd engines in the shop from other engine builders without that plug installed and there was oil pressure but the bearings saw unfiltered oil.

If you stop and look at the pic and see hoe the oil flows its not hard to figue out, WHAT IS STOPPING THE ENGINE FROM OIL PRESSURE!!!! All it does is bypass the filter once its full.

I can tell by this post youR not an engine builder with info posted like this,

RACE ON

CFI-EFI

I don't believe everything I read, however, I do place greater faith in what Chevrolet writes about their own engine than I do in other less reliable sources.

Looking at the picture, I agree it doesn't appear that leaving the plug out would keep oil pressure from building.

And you are correct, that I am not a PROFESSIONAL, full time engine builder. However, I have built my share of engines, and over a period of greater than your 27 years. It is just that *I* haven't put any together with out that plug to observe the consequences first hand. If you noticed, in my first post, I credited "Chevrolet Power", Chevy's own engine book with the information I posted. Here is the page the info came from. Besides the illustration caption, read the last full paragraph in the left column, above the pic, starting with the word "When". If you wish to debate, take it up with Chevrolet Motor Division.



RACE ON!!!

BLOCKMAN

For sure its a type O as where can the oil pressure go. I have seen this posted before and myself and other engine builders have corrected people that post such a statement, The debate is with you not Cheverolet Motor Division as you posted here not them.

CFI-EFI

It may be a mistake, or an error on Chevy's part, but a typo doesn't show both in the text and in the caption.



Apparently, either you didn't read what I posted or your comprehensive capabilities are low. I made the statement on behalf of Chevy. To repeat, I said (scan up and look) "As per "Chevrolet Power".

RACE ON!!!

cardo0

I would have to say Blockman gave us the good information regardless of acusations of his capabilities. Quoting bad information does no-one any good and i question anyones comprehension that does it
Thx to Blockman for his efforts sharing his knowlege and experience here. I think others have good information to share also but don't care to deal with a bashing over trivia.

cardo0

BLOCKMAN

If you new how the SBC oiling system works you should not have even posted that and thats not the first statement an engineer has put in print that I have found issues with!! and won't be the last.

And that has been posted many times on other sites about that misprint.

RACE ON

Sick Z06

IF you all want to be technical. It DOES have an effect on pressure. Once you remeber that the filter (minimally restrictive as it is), does indeed have a parasitic loss.

However the manual page that CFI-EFI posted is INCORRECT.

And I will again say. It has 2 effects. A slight oil pressure change (again by removing a parasitic device from it's chain) and a non-filtration issue. However the technical people can say it has a HP gain, by minimizing parasitic loss.