FenwickHockey65's Great Thread of GM Knowledge

[FenwickHockey65]

Whatever it may turn out to be, it's interesting to note this supposed 2.7L is also slated for application in the 2022 7th gen Camaro...

[FenwickHockey65]

Also, the Niss-I mean, Chevrolet NV2-I mean, City Express is dead.

[DGthe3]

Originally Posted by FenwickHockey65

Also, the Niss-I mean, Chevrolet NV2-I mean, City Express is dead.

I never could figure out the rationale behind letting a competitor rebadge your vehicle. Seems like it would only ever hurt your sales. Dodge did the same thing a few years ago with VW, resulting in the Routan (sp?) minivan. Or Toyota Matrix/Pontiac Vibe from a few years before that. There are lots of other examples, but the practice has never made sense to me.

[KMPrenger]

Wow that Achates design is something else. That kind of power and fuel efficiency sounds amazing. Is the engine itself kind of large and/or heavy?

If this is what GM has up their sleeve I'll be amazed.

I thought I had read it was limited to 3,000 rpm. I wonder what the reason for that is?

[snizzle]

Dang, if it's going into the gen7 Camaro as well, it's likely a turbo 4. Probably looking to eliminate the V6 in the current car and the base 6 in the current truck. Hope i'm wrong. I'd like to see them take a risk on this design.

[DGthe3]

Originally Posted by KMPrenger

Wow that Achates design is something else. That kind of power and fuel efficiency sounds amazing. Is the engine itself kind of large and/or heavy?

If this is what GM has up their sleeve I'll be amazed.

I thought I had read it was limited to 3,000 rpm. I wonder what the reason for that is?

I think opposed piston designs tend to be a little more mass-efficient than similarly powered conventional engines. They're not big, pretty compact actually. But they are an awkward shape. Very tall (or wide, if you lay them down) but kinda small in the other two directions. So putting them lengthwise into a truck would be annoying, the one in the F150 is slanted a bit, but not that big of a deal.


No idea on the rpms though. A few guesses but thats all.

[Royal Tiger]

Originally Posted by DGthe3

I never could figure out the rationale behind letting a competitor rebadge your vehicle. Seems like it would only ever hurt your sales. Dodge did the same thing a few years ago with VW, resulting in the Routan (sp?) minivan. Or Toyota Matrix/Pontiac Vibe from a few years before that. There are lots of other examples, but the practice has never made sense to me.

GMC did it for years with Isuzu medium duty trucks. Same exact truck including the dash and headlights, but different emblems. It allows sales at multiple locations and shares development costs for your Matrix/Vibe example.

[Martinjlm]

Originally Posted by DGthe3

I never could figure out the rationale behind letting a competitor rebadge your vehicle. Seems like it would only ever hurt your sales. Dodge did the same thing a few years ago with VW, resulting in the Routan (sp?) minivan. Or Toyota Matrix/Pontiac Vibe from a few years before that. There are lots of other examples, but the practice has never made sense to me.

For the supplying company, it thins out your fixed costs, especially if it increases your factory utilization. Running a plant at 90% capacity is a lot better than running at 75% capacity. For the receiving company you get to fill a portfolio slot without investing the full cost of engineering a new platform or variant of an existing platform. Can usually be done without too much cannabilization.

The classic example was the Diamond Star Motors triplets. The Eagle Talon / Plymouth Laser / Mitsubishi Eclipse. All produced on the same assembly line, same powertrains, very similar exterior appearance. But customers who bought the Eclipse typically never set foot in a Dodge, Eagle, or Plymouth showroom. And the Eclipse consistently had higher quality reviews than the other two. Go figure.

[DGthe3]

But your costs aren't getting spread out if you're not increasing total sales. Selling in two different markets, or market segments (Toyota iQ & Aston Martin Cygnet, for possibly the most extreme example) can make sense as nearly 100% of those sales are going to be gains.

But I would have to think that if you're interested in something sold by competing brands, you're going to be cross shopping them. Especially now with so many resources available. So a very high percentage of the sales made by your competitor will come directly at your expense. Part cost will be about the same either way because its pretty much the same overall volume, but now you've got lower sales, and associated revenue, for yourself.

If I was an automaker, the smart move feels like forcing competitors to either stay out of a segment, or spend hundreds of millions & about 3 or 4 years of work to get a slice of it. Which is how its done 99.9% of the time.

[Royal Tiger]

Didn’t Volkswagen pay DaimlerChrysler millions for the right to “produce” the Routon? DC makes more vans, more spare parts, and gets cash in its pocket on top? Just a thought.

[Martinjlm]

Originally Posted by DGthe3

But your costs aren't getting spread out if you're not increasing total sales. Selling in two different markets, or market segments (Toyota iQ & Aston Martin Cygnet, for possibly the most extreme example) can make sense as nearly 100% of those sales are going to be gains.

But I would have to think that if you're interested in something sold by competing brands, you're going to be cross shopping them. Especially now with so many resources available. So a very high percentage of the sales made by your competitor will come directly at your expense. Part cost will be about the same either way because its pretty much the same overall volume, but now you've got lower sales, and associated revenue, for yourself.

If I was an automaker, the smart move feels like forcing competitors to either stay out of a segment, or spend hundreds of millions & about 3 or 4 years of work to get a slice of it. Which is how its done 99.9% of the time.

Logic says the part in bold makes sense. Data says that it is often not true. Talk to Toyota Matrix owners about what other vehicles they considered. Most will say Corolla. Second most will say Civic. Third most will say Sentra. You’ll get pretty far down the list before anyone mentions Pontiac Vibe. Ask Pontiac Vibe owners what other vehicles they considered, most will say Aveo/Sonic. Second most will say Pontiac G6. Third most will say Ford Fiesta or Focus. You’ll get pretty far down the list before Toyota Matrix shows up. Only real gear heads know or care that they were built on the same assembly line. And half of them wouldn’t care. And even fewer would know (or care) that Teslas are built in that plant today.

[RLHMARINES]

So the 2.7L 3 cylinder opposed piston engine is in fact a 6 piston engine with untraditional valve placement 2 stroke or am I missing something.:ion:

Can't wait to hear and see more after midnight.

[FenwickHockey65]

http://cadillacsociety.com/2018/03/2...ctures-photos/

2020 CT5.

[camguynj]

Originally Posted by Martinjlm

Here’s some photos of the Achates 2.7L O3 that I took right after their press conference at NAIAS. The F150 it is installed in is definitely a running vehicle. I talked to the engineer on the project after the press conference. It achieved 37 mpg in their testing.

The OP engine design has been around for a looong time. Apparently there are two major issues that Achates have to demonstrate they've overcome ... engine life longevity and emmisions both due to piston/cylinder lubrication. See the following comment on Green Car Congress website in response to Achates announcement.

"The surface-to-volume relationship of the combustion chamber is better during the combustion phase with this arrangement (should favor lower heat losses), but ... call me a skeptic because of the piston porting that is inherent in this design. There is lubrication - oil - on the crank side of the pistons - the piston rings and cylinder walls require lubrication. Every time the piston rings pass the ports, a little bit of oil tends to get out into the port, and that's either going into the cylinder (intake ports) or out the exhaust (exhaust ports). If the rings are supplied with adequate lubrication, the emissions are worse. If the rings are supplied with sparse lubrication, longevity suffers.

Detroit Diesel built piston-ported two-stroke diesel engines for decades, even using electronic injection control towards the end, and with all that experience, could not solve the emissions problems, and switched to four-strokes.

I see nothing about this engine that is indicative of a magic solution to the piston porting emissions versus lubrication trade-off.

I share the same skepticism about ALL of the opposed-piston two-stroke concepts and for the same reasons."