Mobil 1 price at Walmart

I think the build of the engine (machine work, clearances, etc) has a lot to do with the preferred oil viscosity. I have rebuilt a few more than a
handful of engines and done the top end and/or timing sets on a handful more, but chose to have a professional do the build on my 455.

The machine work was done at Larry's Engine and Marine here in Tucson. Larry's has rebuilt literally hundreds of 455 olds engines and countless other
engines for nearly any application you can think of. The assembly was done by Jim Murphy at Calypso Automotive. Jim is very detail oriented and
carefully went through several steps that I probably wouldn't have bothered with.

Larry set up the bearing clearances to run 20W50 oil because of the overly large crankshaft main journals. I use Valvoline VR-1 which has the proper
levels of ZDDP.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
But racing oil has almost no pH stabilizers and is low in detergents, high in antifoam agents. Pretty much the opposite of what an MH engine needs
All to get that elusive ZDDP number. Racing oils are meant to race, drain, repeat.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
> I"m not even sure where to start here....
>
> There are multiple points made and some don't even relate to each other.
>
> First, let's leave RJW out of this discussion because a roller cam is a very different wear issue than a "flat faced follower" as far a wear and
> other issues.
> Second, the 0WXX was an idea that caught on because OEs have been struggling with cold start emissions since they included them in the driving
> cycle tests. But those tests still do not relate to climates colder than LA.
> Third, the reason many of us like the Mobil 1 - 15W50 is not for the dynamic viscosity, it is for the ZDDP that is present in the concentration
> that is close to what was in typical lube oils when our engines were designed.
>
> All of the moving parts may benefit from the additional anti-wear additives of 1200~1500 ppm, but after break-in that benefit may be minimized but
> it is always present. The problem is that the zinc and phosphorus will shorten the life of a catalyst or O2 sensor if the engine consumes much lube
> oil. This is why the EPA demanded the reduction. So, if you have an O2 sensor, you may choose to care.
>
> The 0WXX was born of the cold start issues. Most people do not know that a modern ECU can jump through some amazing hoops. This is why many
> current engines actually turn off (or severely de-power) alternators at start up. They also defuel the engine in an attempt to limit hydrocarbon on
> cold starts. Remember that the exhaust oxidation catalyst won't light until it gets to 350°C. Does it help with lubrication at cold start? Not
> that any test I ever did could detect, and we were looking. I did do a lot of thermal testing because that is the quick way to kill a head gasket.
>
>
> Most of you know that I redid my engine last year. This is/was an engine that we put 70+K plus on and it was rebuilt about 10K on before we got
> it. I did put in a new cam because I did not know what the installed cam was. The followers would still rock on a surface plate. (Flat followers
> are not flat, but are a 5 to 15 foot radius depending on application.) With a top ring step that was between 1 and 3 mils (my glaze breaker with
> ridged stone almost brushed some of them. I could have reused seven of the pistons. The rings were near the wear limit. The cam bearings were
> just fine, but the mains were contaminated with aluminum dust that came from the failed #7 piston. Just for reference, that was engine number 23
> for me and I don't count engine I can carry with one hand. (No tiny engines included.)
>
> Now, where am I going with all this??
> The Oldsmobile and Cadillac engines with the high nickel blocks and careful engineering are so robust, that with the exception of the break-in of
> a flat follower engine (takes about an hour of real run time, but is 90% done in the first 10 minutes), what lube oil you run will probably make
> little difference in the effective service life of your engine. If you have any doubts, get the lube oil analyzed regularly and do not try to push
> the change interval. You are still dealing with a 40year old engine design and unless you do not have much blow-by, the lube oil will be
> contaminated with corrosive by-products.
>
> That is all I have to say about that unless someone has a question or something to add.
>
> Matt

Just one question Matt,

Your statement:
"Does it help with lubrication at cold start? Not that any test I ever did could detect, and we were looking. "

In your testing, did you do cold starts when a test engine sat for perhaps months or up to and more than a year, then look to see if there were wear
issues? Just asking because most of the GMC's here are not daily drivers and sit for long periods between use. Not being critical, just wondering.

--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
We've been over this before. The VR-1 is not strictly a racing oil. It is more of a weekend warrior "racing oil" It does not have the same
properties as oil formulated strictly for race cars. I have been using it for over eight years and it is what Jim Bounds recommended.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
> Just one question Matt,
>
> Your statement:
> "Does it help with lubrication at cold start? Not that any test I ever did could detect, and we were looking. "
>
> In your testing, did you do cold starts when a test engine sat for perhaps months or up to and more than a year, then look to see if there were
> wear issues? Just asking because most of the GMC's here are not daily drivers and sit for long periods between use. Not being critical, just
> wondering.

Larry,

That is a really strange question to ask me. I tried to figure out how to do a test for that for a marine engine adapter company. They were seeing a
lot of premature bearing failures and suspected that this might be due to lube oil starvation at a cold start after a long period of in-attention.
They came to me because I was the guy for cold cycle testing. I could not design a test to do this. I did give them (with the client's approval) the
data from out cold start and deep thermal cycle testing. But those are not the same.

What were those tests?
Cold start tests were just run the engine to a slight over heat, shut it down and force cool it to what ever the system cooling water was (~70/80°F)
then restart and got to WOT/HP peak as soon as it was running...
Deep thermal cycle required a chiller. The test engine would be force cooled to ~0°F and then restarted and immediately pulled to WOT/Torque peak
(highest cylinder pressure) and when coolant was 100°F go to HP peak (greatest heat rejection) until coolant was 225°F. Then shut it down and force
cool again. This test could shake out head gasket issues in as few a 50 cycles, but it could also fail major castings....

As you can tell, neither of these actually addresses your concern. But this is also why I like to start after a long sit by cranking without setting
the choke. Crank it until you at least see lube oil pressure. Then set the choke.

So, I can't actually answer your question. I can tell you that it is sort of a crap-shoot. Any lube oil will run out of the bearings when it is hot.
A less viscous lube oil may pump to the demand points faster, but will have less of the capability for holding surfaces apart when it gets there.
This is one of the places that an anti-wear additive is important.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
OK, I'll be the one to ask: How does Molybdenum Disulphide play in all
that? Does having that coating of slick stuff, that doesn't run off, help
at all? Or does anyone really know? How does it play with the need for
ZDDP? Or does anyone really know?

Personally, I like the stuff and use it sporadically in all my engines.
I've no knowledge to justify my "liking". :-)

Ken H.

On Sat, Apr 27, 2019 at 7:24 PM Matt Colie via Gmclist <

> > Just one question Matt,
> >
> > Your statement:
> > "Does it help with lubrication at cold start? Not that any test I ever
> did could detect, and we were looking. "
> >
> > In your testing, did you do cold starts when a test engine sat for
> perhaps months or up to and more than a year, then look to see if there were
> > wear issues? Just asking because most of the GMC's here are not daily
> drivers and sit for long periods between use. Not being critical, just
> > wondering.
>
> Larry,
>
> That is a really strange question to ask me. I tried to figure out how to
> do a test for that for a marine engine adapter company. They were seeing a
> lot of premature bearing failures and suspected that this might be due to
> lube oil starvation at a cold start after a long period of in-attention.
> They came to me because I was the guy for cold cycle testing. I could not
> design a test to do this. I did give them (with the client's approval) the
> data from out cold start and deep thermal cycle testing. But those are
> not the same.
> ...
>
 
> Just one question Matt,
> Your statement:
> "Does it help with lubrication at cold start? Not that any test I ever did could detect, and we were looking. "
>
> As you can tell, neither of these actually addresses your concern. But this is also why I like to start after a long sit by cranking without
> setting the choke. Crank it until you at least see lube oil pressure. Then set the choke.
> Matt

I have TBI and a switch to turn it's fuel pump "on" or "off". Before a cold start I turn the pump "off" and crank until I see oil pressure on the
gauge. Then I pause a few seconds and then I switch the pump "on" and then crank again. It takes just a few seconds for the engine to start. Not
like the old days with the carburetor. Just what I do for the reasons discussed here..

--
Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com


Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator, Lenzi stuff, Manny Tranny etc.
 
> OK, I'll be the one to ask: How does Molybdenum Disulphide play in all that? Does having that coating of slick stuff, that doesn't run off, help
> at all? Or does anyone really know? How does it play with the need for ZDDP? Or does anyone really know?
>
> Personally, I like the stuff and use it sporadically in all my engines. I've no knowledge to justify my "liking". :)
>
> Ken H.

Ken,

I can provide a lot of an answer, but this is only based on studies that I have read and little personal experience.

Molybdenum Disulphide (here after referred to as MoS2) has been extensively tested.

Yes, it does hang on the surfaces and not run off. This was best demonstrated by a test where irradiated top piston rings were installed so they
could measure the amount of wear metal that came off during the engine running cycle. In this testing, ZDDP, graphite and MoS2 were all tested and
compared to lube oil with no anti-wear additive. All three were improvements with MoS2 a winner. Unfortunately, I don't recall the actual margin,
and I did have the paper in my files three moves ago. It is not the only thing I haven't seen recently.

All of these three are things that get called "metal soap" in that they are metal compounds (either all or part) that have little or no shear strength
and so smear effectively and in doing so prevent actual contact between the loaded surfaces. As it is a metal soap and not a liquid, it cannot run
off the surfaces it has been pushed into. But also, as it has near zero shear strength, it is continually being removed and replaced during an
engines operation. So, the dosing of the lube oil has to be maintained.

All three have been used as additives to engine lube oil, but sadly MoS2 is the most expensive even at the low dosing required. Part of the studies
were done by the USAF, but there again, timing and cost played a big hand. MoS2 is best when used as micron sized particles that are so small that
colloidal action keeps them suspended in the lube oil. The process to manufacture this came on line in the very early 60's. Unfortunately, that is
just the time that piston engines for aircraft were falling out of favor.

If you recall, there are many functions that the lubricating oil preforms in a modern engine and actual surface lubrication is down the list by some.

Sort of in order as I can remember:
1- Cooling - Getting heat out of places
2- Flushing - Getting debris from combustion out of bad places
3- Working fluid - For hydraulic valve lash adjusters and chain tensioners
4- Damping - Just stopping things from banging on each other
5- Preventing metal/metal contact - This is film strength, but grease could do this
6- Hydraulic bearing - This is what happens in journal bearings

Not much of this is anything that any anti-wear additive could actual help. The related problem is that if the particles of any additive are so large
and heavy that they can either interfere with the upper tasks or settle out, then the value of that expensive additive is reduced. Then there is
another more recent issue as it may be that the if the engine is consuming lube oil to any extent, the MoS2 may cause a reduction in effectiveness of
catalysts and O2 sensors. That now qualifies as a big issue to the EPA.

Well, this is a lot for a Sunday morning. I do have other things to do today.

Matt

--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
I think that awakening with no fuel provided during cranking to prime the oil system (assumimg it drained down during sleep) is probably a good idea
for pressure lubed bearings but not so good for pistons , rings, walls and cam. I doubt there is oil being thrown up that high from the journals at
cranking RPM especially if you swear by 20W-xx oil. If nothing good hapens in an idling IC engine (to quote Matt) I wonder how cranking applies.
Personally I like to get to 1500 RPM ASAP to make my crankcase look more like the demonstrator dishwashers with see through doors at the home center.

My racing oil comment is just a heads up to that type as a general poor choice. If I am correct, some of the Valvoline VR1 products are perfectly
acceptable while others are not and race only. Do your research.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
> I think that awakening with no fuel provided during cranking to prime the oil system (assumimg it drained down during sleep) is probably a good
> idea for pressure lubed bearings but not so good for pistons , rings, walls and cam. I doubt there is oil being thrown up that high from the
> journals at cranking RPM especially if you swear by 20W-xx oil. If nothing good hapens in an idling IC engine (to quote Matt) I wonder how cranking
> applies. Personally I like to get to 1500 RPM ASAP to make my crankcase look more like the demonstrator dishwashers with see through doors at the
> home center.

I may be wrong in my approach to cold starts with not sending fuel to the throttle body until after I see oil pressure. However, I doubt that
starting this way causes more wear than when I had a carburetor and choked it to get it running. It only takes maybe 2-3 seconds cranking to see oil
pressure and maybe 1-2 seconds to get a start after switching on the fuel pump. It seems like with a carburetor it took longer then that to get it
started when cold. I might be wrong since its been more than 10 years since I had a carburetor in my GMC. As far as going to 1500 RPM, I think I
have the computer set to go to 1,000 on a cold start. I wonder if I should run that up for starts? That's easy to do with EBL.

--
Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com


Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator, Lenzi stuff, Manny Tranny etc.
 
> I think that awakening with no fuel provided during cranking to prime the oil system (assumimg it drained down during sleep) is probably a good
> idea for pressure lubed bearings but not so good for pistons , rings, walls and cam. I doubt there is oil being thrown up that high from the
> journals at cranking RPM especially if you swear by 20W-xx oil. If nothing good hapens in an idling IC engine (to quote Matt) I wonder how cranking
> applies. Personally I like to get to 1500 RPM ASAP to make my crankcase look more like the demonstrator dishwashers with see through doors at the
> home center.
> My racing oil comment is just a heads up to that type as a general poor choice. If I am correct, some of the Valvoline VR1 products are perfectly
> acceptable while others are not and race only. Do your research.

John,

Your concern for the lack of lubrication during cranking is not without merit, but it is somewhat overblown.

There are two immediate parts to this.
First is that if you have ever cranked an engine with service lube pressure in the system, you would have seen that there is lube oil all over the
place inside the crankcase even at just cranking speeds. There is plenty to get on the cylinder walls and under the piston crown which is where the
lube oil for the rings gets there.
Second is that the power cylinder parts do not have fire load on them. So, the piston cross-head (that part of the side of the piston that manages
the side load caused by the connecting rod angle) has nearly nothing to do and the piston rings do not have any of the fire pressure that is what is
supposed to force them against the cylinder walls to limit blow-by.

Therein is the big difference between cranking and idling. As soon as you have fire load, everything changes.
There is a sub-set of idling engine problems that are related to the internal velocities not being high enough to create the hydraulic wedges that
actually support the majority of the loads in an engine and this is tough on the journal bearings and non-roller cam followers.

If you are concerned when started a dry engine, you could always do what engine professionals all do, and that is pre-oil the upper cylinder so the
rings are never dry. This is not all that tough to do, but it is vastly inconvenient.

Matt

--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
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