high oil pressure after engine rebuild

Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's, Olds 98 91-96, Buick Lesabres and Park Avenue 91-96. Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.
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grey3800
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Posts: 302
Joined: Mon May 26, 2008 9:36 pm
Year and Trim: 1993 SE L27
Location: Southern California

high oil pressure after engine rebuild

Post by grey3800 »

Hello Everyone,

Just finished rebuilding my motor. After a lifter failure & subsequent damage, the engine has been rebuilt.

Work done to engine:
New camshaft
New lifters
New pushrods
New timing chain & tensioner
Polished crank
New pistons & rings
New bearings
Cylinders bored 20 over
heads rebuilt, resurfaced
Oil pump rebuild kit installed
New oil pressure sender unit

After running it for about 100miles, the pressure range is between 80-95psi. Consistently about 85psi while cruising. This is running 5-30W oil.

Does this sound too high? could this work above cause a high change in pressure? Can I keep running like this? Prior to the rebuild, 45psi was normally seen.
-Patrick
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Current (work): 1993 SE L27 --- 275,000 miles and counting.
Current (Fun) : 2009 G8 GT; 6-speed manual; 3.45;
Retired(sold): 1988 LE LN3 --- 273,000 miles of fun, Farewell....
DarkShadow
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Joined: Thu May 22, 2008 1:09 am
Year and Trim: 90 SSE / L67 4T65E-HD
Location: Berkeley, IL

Re: high oil pressure after engine rebuild

Post by DarkShadow »

Gm Specifies a minimum of 60psi at 2000rpm, I constantly maxed out the 80psi oil pressure guage on my old bonneville at cruising speed with a good sending unit. Your high pressure is more than likely a healthy oil pump and a new engine with tight clearances, it will wear in.
Last edited by DarkShadow on Wed Aug 11, 2010 2:54 am, edited 1 time in total.
90 Pontiac Bonneville SSE Series 2 L67/4T65-E HD [Frankenbonne 2.0] Swap complete, currently whomping on unsuspecting hondas.
85 Chevrolet Celebrity 2.8 2bbl/440T4
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