My Chevy Issue, cont’d…

[Ματθιας]

I just realized that 1.5L isn't even 100 cubic inches. That's TINY. Add a turbo, for that little motor to move that weight... Yeah, I don't know about longevity.

 

[TX-Dennis]

Yup. A friend has a tiny Ford Ecosport that has a 1.0 liter 3 cyl. turbo. Talk about tiny! The engine has already been replaced under warranty once.

 

[Oldengineer]

When you decide to make a little machine do big work, you need to “gold plate” the hardware. These upgrades are expensive. We’re talking about sil1 intake valves, nimonic 80 exhaust valves, overplated bearings, forged pistons, etc, etc. You can’t just hang a turbocharger on the side of the engine. If you do,,,,, well we know that the science experiment has been put on the back of the customer.

 

[LVSteve]

I just realized that 1.5L isn't even 100 cubic inches. That's TINY. Add a turbo, for that little motor to move that weight... Yeah, I don't know about longevity.

Chevy have been trying to make small turbo engines to game the EPA regs for over 15 years. Their mistake has been that because of their badge, they have a fixation with using 87 octane gas. Bad plan made worse by the increasing lard in their body designs. GM sedans got stupid heavy from about 2010 on. Somehow, Accords, Camrys, and Sonatas didn't.

VW have not had the same issues with their small turbos by not making them as small as GM. GM tries to use 1.5 liter motors, while VW uses 1.8 and 2.0 motors. Honda have recently started recommending 91 octane for their 1.5 turbo in the Accord. Bijou cluette, non?

 

[Oldengineer]

The way that you determine that an engine is durable is through a process called Design Verification (DV). There are many tests involved (at least at Ford) and the one that quickly separates the “men from the boys” is called a 100 hour FIE. The test basically uses a dynamometer and runs the engine at wide open throttle for 100 hours, alternating between peak torque and peak horsepower. Usually 3 engines that pass with acceptable tear down analysis is a pretty good indicator that the base engine is solid.

 

[The Norseman]

Engineers don’t know

I’ll tell you the real way of testing a vehicle,
give it to my cousins out on the Ranch or
Farm for 6 months.

Ranch work or Farm work plus 60mph on
dusty, wash board gravel and dirt roads
will tell you a lot immediately, and set
some on fire and giggle hoses loose.

 

[venomballistics]

When you decide to make a little machine do big work, you need to “gold plate” the hardware. These upgrades are expensive. We’re talking about sil1 intake valves, nimonic 80 exhaust valves, overplated bearings, forged pistons, etc, etc. You can’t just hang a turbocharger on the side of the engine. If you do,,,,, well we know that the science experiment has been put on the back of the customer.

I figured forged popcans would be a common sense sort of thing.
It's pretty much gospel with anything forced induction.
But we seem to be running into all the same care issues I found in the Buick Regal .... only worse.
to quote Wikipedia pertaining to this series of engines ....

"The GM Small Gasoline Engine (SGE) is a family of small-displacement, inline three- and four-cylinder gasoline engines ranging from 1.0 L to 1.5 L, developed by Adam Opel AG, Shanghai Automotive Industry Corporation......."
The chassis is the lowest bidder out of Germany populated by Chinese parts.
It's painful enough having to revise a production screwup when it's your own creation ... These things turned into third party assemblies. So now it's not only a matter of admitting to a defect, revision is not an internal affair.
I think the best route to these design goals might have been through Yamaha tapping their sport bike engine experience.

 

[WR Moore]

DEEP in the last century I learned about highly tuned small displacement engines at the same time I learned about UK sourced vehicles. The issue with the HTSDE is that everything has to work perfectly all the time and maintenance is a HUGE issue. Also, not all motor oils are created equal. The larger displacement, less heavily stressed engine is going to last longer.

Proper design/materials matter. Which is where the bean counters get their whacks in. All the turbo (diesel) engines I've ever worked with have sodium filled exhaust valve stems and use (relatively) exotic alloys. Those are items you're unlikely to see in a base model engine.

While fuel/air mixture in the affected cylinders in the video might be a problem, one of the primary causes of piston failure/heat damage is ignition timing. These days that likely involves a slew of sensors and the engine control module. All of which have to have the correct programming and work correctly. Not to mention some issues with actual octane ratings of what gets put in the tank. An extra buck or few per tank is cheaper than an engine.

ETA: an exhaust temperature gauge should be on any turbo engine. Watching those can be really educational, especially when pulling grades. As is an engine temperature gauge, although those are rare these days. The vehicle might show no performance changes, but critical temperatures can be reached especially at altitude-like Denver.

2nd ETA: the video shows the engine block to be an open deck. That is, the cylinders are free standing and don't attach to the block at the top. Companies that were using that design on normally aspirated engines quit doing so because of head gasket and cylinder warping issues. They NEVER used that design on tubro engines.

 

[Oldengineer]

It’s important to recognize that the small car segment is a profit LOSER and is necessary to keep the high profit, low fuel economy vehicles in business. It’s called CAFE — Corporate Average Fuel Economy. If you’re losing money on every vehicle you sell, it’s imperative that you cut your loses and put absolutely nothing extra into the design, development, and manufacturing. Bare bones…..that’s it. What could possibly go wrong?