Kodiak Bear

In a now locked thread several of us got a discussion theme going questioning if a developed C7 chassis, maybe the Al version, is able to support both a FE & ME. Steven Bell has indicated that it is within the protocal of the site for us to continue that discussion theme in a new thread, subject to the usual rules.

"Originally Posted by Kodiak Bear
Thanks
Went back and did a bit of research. The C7 chassis is an evolution of the "backbone" design originally proposed by Lotus, then owned by GM, for the C5. While a big fuss was made over the hydroforming of the side rails which made the chassis economically feasible for GM production rates, it is a backbone design. Interesting SAE papers out there on the C5 chassis.
Lotus later did the Indy mid rear car, for GM, on a backbone design. This evolved into a much more production ready ME, the CERV III design, by GM, again on a backbone design. I'm stretching it a bit here because I don't know the details of the present C7 chassis but that chassis appears to be adaptable to FE and ME because the backbone design enables replacement of the front and rear portions while maintaining the cab which contains the backbone.
So, the FE could well be more than a transition car, or at least has the potential to remain in production as a seperate line along with the ME because both can be based on the same backbone chassis architecture. That solves the problem of engineering resources as much work is transferable accross the two, the FE and ME.
It also might explain the rumors of chassis issues. Sharing a basic chassis architecture sounds easy, but the details have got to be very complex."

@CRABBYJ how about jumping in?

Anyone else?

Darion

Sharing basic chassis structure between FE and ME doesn't sound simple in the least bit. Not saying it cant be done but simple, no way.

PC

Kodiak Bear

Facinating, isn't it? Couple of other things. Take a look at the work Lotus did with a backbone chassis on various "street" cars with the backbone chassis .

Also, someone on the previous thread said the C7 Al chassis is welded instead of using continuous hydroformed tubes. Be a neat way to get some street miles over the years to see if the chassis can take what is needed with welds at those points. They happen to the points where different modules would be attached for FE and ME.

Unfortunately logic does need some confirming data, so it's all speculation!

CRABBYJ posted some articles from MT on the subject in the other thread. I hope he adds them here.

I wonder if there's away those posts by folks interested in this subject could be transfered "automatically" from the other thread, but it would have to be done with their permission. .

Quinten33

Suns_PSD

Ludicrous idea that would result in insane compromises for both structures.

Not ever going to happen.

CRABBYJ

Kodiak Bear

Thanks for all the postings.
Scenario Thinking.
A few years ago, the Vett team realized two things. The C7 was not going to be completive in racing against the mid-rear cars for much longer and the C7 had reached a point of diminishing returns on investment for further development. However, there is a market for both FE and ME cars. By sharing a common chassis architecture, some engines and other costly parts, GM would be able to build cars to satisfy both FE and ME markets, and keep successfully racing, at the price point the team wanted on the same production line. As a proof of concept for some of the key features the chassis would have to successfully demonstrate, the Vett Team produced the C7 Al chassis. This chassis has been in the hands of the public and successfully proved the necessary key solutions to the engineering problems. The envisioned Vett chassis is a backbone based three module design with the center cab/backbone common to both FE and ME cars.
Vett will introduce two “new” Vetts, a FE and a ME on this new chassis architecture.
The FE could get the name Manta Ray as a continuation of the Ray family of FE cars. See the Manta Ray II show car.
Don’t know about the naming of the ME, but I’m betting against Zora. However notice that performance packages are Z-xxx, and the alleged control numbers are “Y2XX” for the "new" standard front-engine car and “ZERV” for the mid-engine car. I think the Zora underground slips a Z in once in a while.
.
Side Bar Comments:
· The Porsche 911 RSR is a ME car. The engine has been moved within the ISMA rules to a mid-rear position.
· "In 2011, a new Corvette Daytona Prototype was introduced whose chassis was a joint development between Cheever Racing’s Coyote manufacturing and GM’s de facto racing squad of Pratt and Miller". GM’s Jim Campbell made a speech at the event.

Reminder
The 1990 CERV III Corvette is an interesting concept

What EVIDENCE exists that supports or challenges this Scenero?

WhiteDiamond

ABSOLUTELY!!! Not sure why the discussion continues on this idea, but this is not a money maker for GM in the way BGA is set up.........

RoketRdr

Not sure why you continue to spew the opposing garbage that you do as if its a gospel because you're incorrect.

Speednet

It would like like one of those drawings where you turn it upside down and it becomes a different face.

WhiteDiamond

The release by GM will show just how WRONG you are. This is a business tasked with making money. They are more aware of this now than any other time in their history. One C8, it is ME and you have no clue.

Many post on here like they know, but they don't. Production reality, engineering reality. and cost reality pretty much backed up by the mules seen running around, show your point to be argumentative at best and clueless in reality.

KnightDriveTV

Since you have all the clue and have it figured out, can you explain, in detail the manufacturing architecture model that GM has switched to called the "vehicle set strategy" which is in like with the MQB approach by VW. Mary Barra and Mark Reuss have spoken extensively about plant retooling and major reinvestment, in order to stay relevant, by creating multiple platforms from a single core architecture. I'm sure you know, this isn't to be confused with a Cadillac Cimarron and a Chevy Cavalier, this goes to the pickup points within the chassis core, to create two very different looking vehicles, from a core set of engineering, in order to drastically reduce engineering costs. Can you describe how that future architecture will be implemented please?

From an investor briefing with Mark Reuss: And while tearing up and retooling dozens of GM assembly plants could cost billions of dollars, “once done, the economies of scale will be massive - if everything works properly,” he [Mark] said.

Bowling Green was the first recipient of this massive restructuring, so can you elaborate on what was implemented and how it will be shown in the platform, in the future. Seems you imply that making an ME with an FE is quite impossible.

I'd direct you to the first known ME mule which was a holden ute with a very clear C7 center capsule/roof, which coincides with the MQB architecture approach. While BMW has done shock tower to shock tower, GM is implementing three sections to its vehicle toolkit approach, I'm sure as you know. It's the engine compartment, passenger compartment and storage compartment module.

Please give us your engineering insight so we can understand why we're so wrong and you're so right, to the extent you call people clueless morons and idiots.

WhiteDiamond

The C8 debut will solve all your mis-conceptions. Until then, I actually enjoy reading the comment by people who obviously have no clue about production realityies and and engineering costs to get theere.


Let me say this, all C8 hardware has a production schedule submitted by GM at this point. Sure, there may be some issues on that timeline, but GM is pushing hard to get those issues fixed.

KnightDriveTV

As usual...nothing substantive...just a simple "nuh uh" Can't even spell realities correctly, so you're going right down hill friend.

How about this..."if you say so"...

I think maybe based upon your simplified responses, we need to be clearer for you. The Mid Engine car WILL debut first, but a subsequent front engine platform will result. Corvette teams resources went to the development of the ME car, then as production hits and development is done, the work on the front engine platform will begin. In some ways, I'm sure it likely has. The mid engine and front engine will actively be built, side by side, within the same manufacturing plant....fact.

Kodiak Bear

I don't know how credible this site is but try it.
https://www.motorauthority.com/news/...hots-and-video
The accompanying writeup makes the following points.
"General Motors had started work on a mid-engine design for the C7 but ended up scrapping the plans in the tumult of the 2009 bankruptcy, with the C7 we ended up with being somewhat of a placeholder."
"We hear the basis for the car’s mid-engine platform will be the C7’s aluminum spaceframe structure rather than a completely new design."

One point. it is not a space frame chassis but rather a backbone chassis according to Dave McLellan retired Corvette Chief Engineer in his book, Corvette from the Inside.