[C2] 1965 L79 Oil Gauge (60 or 80)
Team Owner
Joined: Mar 2003
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From: Greenville, Indiana
I'm not interested in a debate on this but the GM AMA specs for 1965 show a six quart (5/!) crankcase capacity for the L-79 so at least at some point in time, it was a gleam in someone's eye.
Team Owner
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From: Sitting in his Nowhere land Hanover Pa
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Well that proves Larry’s point. So wonder when GM decided to use a four quart pan on the L79 and if this has anything to do with your question about the 60 and 80lb gauge for each pan.
Thread Starter
Pro
Joined: Nov 2007
Posts: 534
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From: Conway SC
Thank you for your valuable input & offer to relay contact info, I think my best choice it to just go with the 80 lb gauge, more for my own peace of mind than any other reason, hopefully I can return the favor one day.
I went back and rechecked Rick Miller's and Noland's Books. Had a bit more time to search. Nothing I could find in Noland's Restoration Book about the 60 or 80 psi oil pressure gage changes.
However in Rick's Book I found two references to the L-79 with the different oil pressure gages that i did not find earlier. One was on page 65 regarding inspecting a prospective corvette for purchase. Rick stated here that some 1965 L-79 cars had an 80 psi oil pressure gage and early L-79 also had the low 5300 RPM redline tachometer.
On page 140 regarding the 1965 specific model year corvette, Rick showed a picture of the instrument cluster of a 1965 car (engine/car not identified) that had a 5300 RPM redline tachometer and a 80 psi oil pressure gage. Rick stated that this suggested that it was an early production 327/350 (L-79) engine.
So there is evidence from his book as well as forum members midstyle and cblankin that the 80 psi oil pressure gage did exist from the factory.
There is no additional knowledge I can find that ties this difference to a particular VIN range or month of production. Midstyle's picture shows the higher 6000 RPM redline tach for the L-79 along with the 80 psi oil gage..........so the oil pressure and tach redline changes were not done together or simultaneously.
The NCRS 1965 Team Leader may have additional info and could be contacted. His name is K.C. Strawmyre from Newburg, Pennsylvania. You can PM me for contact information.
However in Rick's Book I found two references to the L-79 with the different oil pressure gages that i did not find earlier. One was on page 65 regarding inspecting a prospective corvette for purchase. Rick stated here that some 1965 L-79 cars had an 80 psi oil pressure gage and early L-79 also had the low 5300 RPM redline tachometer.
On page 140 regarding the 1965 specific model year corvette, Rick showed a picture of the instrument cluster of a 1965 car (engine/car not identified) that had a 5300 RPM redline tachometer and a 80 psi oil pressure gage. Rick stated that this suggested that it was an early production 327/350 (L-79) engine.
So there is evidence from his book as well as forum members midstyle and cblankin that the 80 psi oil pressure gage did exist from the factory.
There is no additional knowledge I can find that ties this difference to a particular VIN range or month of production. Midstyle's picture shows the higher 6000 RPM redline tach for the L-79 along with the 80 psi oil gage..........so the oil pressure and tach redline changes were not done together or simultaneously.
The NCRS 1965 Team Leader may have additional info and could be contacted. His name is K.C. Strawmyre from Newburg, Pennsylvania. You can PM me for contact information.
Drifting
Joined: Jun 2002
Posts: 1,450
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From: Glendale AZ
I believe I recall the Service News announcing the availability of Power Steering with the L79 in March 1965.
I can also tell you that L79 #23561 has a 1966 80 lb oil gauge in an instrument panel that I recall is stamped 27 July 1965.
I can also tell you that L79 #23561 has a 1966 80 lb oil gauge in an instrument panel that I recall is stamped 27 July 1965.
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From: Bowling Green, Kentucky
FWIW.
Larry
Race Director
Joined: Apr 2005
Posts: 11,277
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From: Bowling Green, Kentucky
That is what I would do. 
Larry
PS: I would likely also install the HP oil pump.
Last edited by Powershift; May 21, 2018 at 02:31 PM.
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Thread Starter
Pro
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From: Conway SC
Pro
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From: Calgary Alberta
Last edited by midstyle; May 21, 2018 at 06:50 PM.
Drifting
Joined: Jun 2006
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From: Durham ON
However in Rick's Book I found two references to the L-79 with the different oil pressure gages that i did not find earlier. One was on page 65 regarding inspecting a prospective corvette for purchase. Rick stated here that some 1965 L-79 cars had an 80 psi oil pressure gage and early L-79 also had the low 5300 RPM redline tachometer.
On page 140 regarding the 1965 specific model year corvette, Rick showed a picture of the instrument cluster of a 1965 car (engine/car not identified) that had a 5300 RPM redline tachometer and a 80 psi oil pressure gage. Rick stated that this suggested that it was an early production 327/350 (L-79) engine.
Last edited by DSR; May 22, 2018 at 01:34 PM. Reason: More info
Instructor
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Team Owner
Joined: Mar 2003
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From: Greenville, Indiana
Does the AIM show a cluster assembly code for each engine? Does the AIM cluster listing for L 79 have a revision usage date?
If not, that would seem to suggest several reasons for the confusion.
Whoever the vendor that put the clusters together decided that either gauge would work for L 79.
The vendor had employees who were careless and put in the wrong gauge. Either because they ran out of the right ones or just didn't GAS.
Somewhere in Chevrolet (or other) service, someone replaced the original gauge and/or the whole cluster assembly.
It was common in the '60's in Dearborn to approve "upgrades" by the QC engineer on the floor if the substitution was "better" than the base requirement.
I know engineering is supposed to approve (with paperwork) all changes that vary from engineering intent. It didn't always happen that way.
If not, that would seem to suggest several reasons for the confusion.
Whoever the vendor that put the clusters together decided that either gauge would work for L 79.
The vendor had employees who were careless and put in the wrong gauge. Either because they ran out of the right ones or just didn't GAS.
Somewhere in Chevrolet (or other) service, someone replaced the original gauge and/or the whole cluster assembly.
It was common in the '60's in Dearborn to approve "upgrades" by the QC engineer on the floor if the substitution was "better" than the base requirement.
I know engineering is supposed to approve (with paperwork) all changes that vary from engineering intent. It didn't always happen that way.
Last edited by MikeM; May 23, 2018 at 06:16 PM.