Yeah, the Vega project was the work of GM corporate and handed over to Chevy with little time left for proper development and a tight budget . The alloy block was at least partially designed by Alcoa .Besides the bore coating the open deck design would warp and a new head gasket or even milling would not last… With the Pinto 2.0 engine the cams starting failing in about 20,000 miles or less.
Back in the early 1970s, the average life expectancy of an American production motor was about 75,000 miles before major work was required. Less then 10% made it to 100,000 miles. It was everyone expected back then, and was pretty much accepted that if your car made it to 60,000 it wasn't long for the world. Everybody had lots of excuses why the motors failed back then. 10 years ago, those numbers were more then double, but these days they are dropping back to about double. People are still making all kinds of excuses. Every manufacturer has made at least one mistake motor, but some manufacturers are more mistake prone then others.
Gene, computerized machining and engine management has extended engine life exponentially.. I remember the stripes of oil down the center of a lane, how you watched your step in a parking lot, how the fuel island had quarts of oil ready for sale..Computer aided design, computerized precision in mass production and computerized engine management tightened everything..
I got out in 2012! We had just got two engines that were multi-placed! Against my wishes. It is an extremely complicated way of doing a simple thing! Just about got the hang of it , then I retired. I hear the new guy can’t keep the engines running! Progress! Lol Right! Bones
I made a lot of money in the late 70's early 80's swapping odd fire 231 V6 Buick engines, replacing nylon toothed timing gears and wiped lobe camshafts on V8 chevys. Then I decided cars were turning into nightmares and switched to trucks, in 2010 the diesels caught up and passed any growing pains cars had in the 80's..................
I agree, I was a mechanic until 2008. It sure seems we have turned a corner around 2010 and things are not lasting as long as they did previously. Removing much of the ZDDP from oil may be a contributing factor. Diesel emissions @Wrench97 have been totally out of hand with all this EGR, after treatment, DEF, SCR, alphabet soup.... Sad really. We lowered the piston ring tension to save fuel, then they had to take the ZDDP out of oil because it poisons the catalytic converter, due to low ring tension and oil making it into the combustion chamber in large doses. With little ZDDP we now have much higher cold start wear. Downward spiral. Blah blah blah.
I also don't discount the effect the current crop of 700+ hp has on the life expectance of the modern motors. Logic says that when you hang a supercharger on a motor, you shorten its life dramatically. Then add in all the short cuts (sorry, add in the effects of gaining more mpg , which doesn't seem to be happening like they say), also has to have an effect on the length of life. The sad part is the current crop of stuff is still 2x better then anything (with maybe a few exceptions) produced before 1970. AHHHH! But lets get back to bashing all the mistake motors, that is more traditional.
I forgot about the little Ford six first years, the 170 and 144 had a tough time keeping the bottom end lubed and bearings in it.
from the sidelines, my guess on modern longevity dropping is two-fold; getting the engines up to temp ASAP and running them on the edge temp-wise means any issue goes into overheat the bean counters are trimming the time to build, QA and tooling and experience.
My dad had one when he worked in a Chevy garage with his two brothers. He said the rod journals were too small and didn't last. He would replace them with Whippet bearings. He converted it into a wrecker for their garage.
I remember back in the mid 1970's a couple made the front page of the local newspaper when their Pontiac turned 100,000 miles. That was an amazing feat in those days!
There’s more than a fair argument that the ford Flathead V8 makes a list like this..a 96% casting rejection rate in ‘32, high oil consumption handled by ‘37, prone to overheat and casting failure its entire run. Only Ford had enough money to see it through in the beginning. Power to weight ratio is terrible too Sexy as hell no doubt, sound good too..
Although the old Chevy 6’s were supposed to be reliable, I never understood why the goofy complicated oiling system with scoops ,troughs, and pressure mains. far as I know, the rest of GM then was typical pressure oiling..
Ford Canada used the flathead through 54, cars and trucks. The Y block was introduced in Canada in 55. In fact Ford Canada did not have a 6 cyl until 1956 or 57. All fords had flatheads.
I'll throw out a traditional era engine- the 41-48 Lincoln V12. Based on a stretched Ford flathead block, they were prone to overheating even when new. They didn't get the blocks clean of mold sand. Bore was too small to produce any decent horsepower and weight was too heavy. Most didn't make it to 50,000 miles without being rebuilt or being replaced by an OHV Caddy or Olds engine. When new they were supposedly a smooth running engine, just not up to the task of pulling a nearly 4000 lb car around at highway speeds.
It's strange looking at these big old heavy engines with tiny bores. It appears that with little effort the designers could have made the cylinders half an inch or more larger without increasing the engines' overall dimensions.
My buddy was a victim of the Vega when we were kids. We were coming home from the hash bash in Ann Arbor and the motor let go. No tears as we weren't feeling much pain and we just left it on the side of the highway.
The anemic GM 2.8 liter V6 crankshaft splitter.. I had an 86 S10 with the 2.8. It was at 102,000 miles when the crank let go..
The Jalopy Journal
