I found this on the Scoggin-Dickey page about an oil passage plug above the rear main that should be installed, its about half way down this page:
http://www.sdpc2000.com/htm/techtip....Torque%20Specs
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It says on "Bare Blocks" it is not installed from the factory, what about short blocks/rotating assemblies?
I did not install one on my ZZ4 short block/rotating assembly, did anyone else?
My oil pressure seems low compared to all of my previous motors, its 12-15# at idle.
I asked SDPC tech line, but did not get a real competent sounding answer. Hate to pull it apart again..

 

Yike,s I have the ZZ4 crate motor, and I have good oil pressure (almost 30psi at idle). Almost sounds like something wasn't done on your motor.

 

I'm guessing you got a bare block and ZZ4 rotating assembly separately and then assembled it yourself? Because my ZZ3 shortblock's oil pressure is at 30 psi at idle fully warmed up, so I'm assuming this plug is installed on mine from GM (I would hope so!) It's probably safe to say then this plug is in all their shortblocks.

If you didn't install the plug you're basically bypassing the oil filter and circulating unfiltered oil through your block. I know it's a PITA but I'd tear it apart and install the plug.

 

Actually, no, the rotating assembly was installed, it was really a shortblock with the cam removed.
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The thing is I have real good oil pressure until it gets hot and has a few higher revs on it, then it drops like a rock.
The guy at SD said he's seen several ZZ4/ZZ3's that barely have 10psi at idle

 

Yeah, that ain't right. I've got a '79 vette with a 350 that's on its last legs and it can usually muster 20psi at warm idle (never goes above 30 though).

 

Well I popped the oil off again, and the plug was already installed so that ain't the reason for the low oil pressure. Guess its just the sloppiness at GM Mexico that built the ZZ4....won't be buying another block from GM again. What gets me is at cold startup before everything expands I'm getting 65+# of oil pressure then when it gets hot its about 15-20# with a brand new HV/HP oil pump!??
Everything is brand new in this motor, I've inspected all the main journals and rod journals and all seem ok, a couple were discolored to a gold tint but were still smooth.

 

Hmm.

The discolored tint seems indicative to me of residue from overheated oil. How hot does your motor get?

Here's another question, when was your ZZ4 motor built? Mine's more than 3 years old now.

 

It runs at about 200 degrees F, never over that.
I received the ZZ4 block and rotating in July from Scoggin-Dickey last year and installed it in Oct. last year.
Only 2 main journals, #3 &4 had the gold discoloration, all others and rod journals were gray with little scratching.

 

I would check the bearing clearance on those two bearings.