New oil in an 50s car

[double vanos]

I was watching periscope films on you tube and came across an old Pontiac ad. It touted the fact that the engine would go 100,000 miles between overhauls.
We're oil heads here and know that motor oil in the early 50s was primitive to say the least, but it's what was used to get that Pontiac to 100k miles.

Question: would that exact same engine (car) go any farther on today's advanced oils? If it would, how much? Keep in mind we're talking oil bath air cleaners, blow by gases emitted into the atmosphere, carbs, leaded gas and oil filters of that day.
This question crossed my mind while watching this film. There's also a film ( I think it was Citgo) showing oil testing and development in the early 50s - oils back then weren't anywhere as good as they are today.

Kind of a brain teaser, how far would it go?

 

[krismoriah72]

I would say look less at the oil and more to the fuel contamination for longevity.

Same engine with an EFI carb conversion plus modern oil would probably at least double or triple its life.

Those old carbs, plus points, and worn copper plugs were a recipe for fuel contamination.

I would rather have the gasoline from back then though.

 

[aquariuscsm]

Is the machining process of first more precise to make the engine last longer? I'm sure the oil is leaps and bounds better today!

 

[Cujet]

Well, leaded fuel in a Rotax 912/914 aircraft engine shortens the life markedly, possibly by half. So I'd guess that as mentioned above, fuel contamination due to carb issues and leaded fuel were likely contributors to the short engine life.

It's also good to recognize that many hotrod engines are old technology. Using pushrods, flat tappet cams, cast iron blocks and heads, cast iron 5/64ths rings and cast aluminum pistons. They seem to hold up quite well on today's oils and fuels.

Many of us that have operated such old engines get great service from Mobil 1, 15W-50.

 

[Lubener]

They must mean the lower end. Engines of that era were lucky to go beyond 50k without needing a valve job.

 

[carviewsonic]

Using the same OCI's I would guess maybe only 10k to 20k miles further (with a valve job), but no other internal work. Even modern oil could only do so much to overcome often overly rich carburetion, and poor air/oil filtration. I'm guessing the metallurgy wasn't as advanced back then either.

 

[eljefino]

Originally Posted by carviewsonic
I'm guessing the metallurgy wasn't as advanced back then either.


Though I'm sure you're right, "value engineering" wasn't as "advanced", either, so they may have (accidentally) made stuff extra high quality because they didn't know where to cut corners.

Snobs used to brag how their Olds 350 had more nickel in the block than a Chevy 350. Then someone got a Chevy motor in their Olds and sued GM over it.

 

[CR94]

Improved air filtering should get more credit for improvements in engine durability. Carburetors and points ignition were handicaps only if not set up and maintained properly.

I knew of several 1950s engines that went beyond 100k without becoming heavy smokers or any other problems. My parents' 1954 Chevy (same as listed below) did not, mainly because of the combination of frequenting dusty gravel roads, dubious filtration, and failure to keep valve clearances adjusted.

 

[PimTac]

One of the biggest reasons for fuel dilution was the driver pulling out the choke when they started up but forgetting to push it back in at the appropriate time.

 

[Chris142]

Originally Posted by aquariuscsm
Is the machining process of first more precise to make the engine last longer? I'm sure the oil is leaps and bounds better today!

Not really. They had machines and measuring tools back then.

 

[double vanos]

Well the comments here mirror my thoughts exactly. Not only was the oil not so great but the other factors mentioned also led to the need for overhaul in the early 50s.

As an aside when I was 16,I had 2 friends whose dads bought company cars when they were turned in; one was a ‘67 Plymouth 318 sedan stand shift car from Sclumberger, the other bought a retired Harris county sheriff car (‘68 biscane) with a big block engine. They were at the 100k mark and both ran very well. This was in 1970. So not only did oil and manufacturing and improved parts help but both had religious 3k oil changes. So from the early 50s to the middle to late 60s there was a lot of improvement in both.

 

[Dinoburner]

Back in the fifties cars that passed 90,000 mile were said to have gone around the world 3 times and were considered near done. The oil filters were bypass type that filtered some of the oil some of the time. On a rebuild the oil pan would have a half inch of gray colored lead in the bottom. Properly adjusted valves lasted due to the lead lubrication but one would have to occasionally need to blow out the carbon and lead with a full throttle run once in a while.

 

[CR94]

Originally Posted by PimTac
One of the biggest reasons for fuel dilution was the driver pulling out the choke when they started up but forgetting to push it back in at the appropriate time.
Probably true of vehicles with manual chokes. However, most American cars had automatic chokes by the mid-1950s. Cheap foreign cars (including my '72 Subaru ), trucks (including my parents' 1966 F-100) and tractors did not until much later.