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This isn't a guarantee, but what if this came to be? Good idea? Bad
idea?
Someone at GM has been wanting to do this for a long time.
http://www.corvettes.sk/images/Prototypes/XP819/1964%20XP-819_01.jpg
What
Certainly different, but Corvettes have always been front engined, so it
could spark some controversy between enthusiasts....
Cliffy
Eh I don't like the reasons for the shift really. I think they should stick
to the corvettes front engined setup unless going mid engined results in
gains. Im not sure it would, it very well could though. I like the looks of
a long hood, that looks right to me. Maybe they could just move the driver
and passenger and engine back to achieve the same result.
I think they should move the engine back and make the driveline more of a
stressed structural components to save weight. I like where they were going
with the engine solid to the rear of the car. Great idea. I think they
should build on it.
rudypoochris
come again?
windsonian
Well if you look at the driveline of a C6 it is solid from engine to rear
axle. The driveshaft is inside a metal case that bolts to the engine which
bolts to the transaxle. This helps keep good balance and provides rigidity.
I was suggesting they slide the engine even farther back and go with a
longer hood and make the driveline more of a structural member to save
weight elsewhere.
rudypoochris
I don't really believe any of it.
Mathew
So you want to use the drivetrain to take the stresses of the car's weight
and inertia?? Don't you think you're going to drastically reduce the life
of your drive components doing that? Can you imagine the cyclic
stresses/strains? The necessity to over-design to remain under infinite
fatigue life would hugely increase the weight of the drivetrain, thus
defeating the purpose.
[Disclaimer]: obviously I'm making these comments without any calcs, but
intuitively it seems (to me) crazy to use your transmission components for
transferring non-drive related stresses.
Out of curiosity, by using this method, where would you make the
distinction/joint between suspended and non-suspended transmission
components?
windsonian
The transmission in the C6 is mounted in the rear and connected to the
engine via "torque tube". It was designed to keep the 50/50 weight ratio to
the front and rear. The torque tube is mounted to the the engine much like
the manner of a bell housing would be. A ball and socket type of joint
called a "torque ball" is used at one end of the torque tube to allow
relative motion between the axle and transmission due to suspension
travel.
http://www.vnexpress.net/Vietnam/Oto-Xe-may/2004/03/3B9D0C45/C6_chassis_1B.
jpg
The torque tube is hollow and houses a more traditional driveshaft. There
is consequently no stress on the "drive line". The design has been used in
Porsche 944 if you're somewhat familiar with that setup.
DSMer
Ummmm... I know exactly what he was talking about... but it seemed from his
post that he wanted the driveline to be structural..... In fact, that's
exactly what he said.
So, saying "There is consequently no stress on the "drive line"."
contradicts what he said.
Chris, I'm interested to hear your ideas. Were you, in fact, referring to
what DSMer's talking about, and maintaining the rigid shaft housing, but
using it for structural reasons? Or did you actually want to transfer
structural stresses through the drivetrain components?
windsonian
Stop attempting to be a stickler. If you knew what he was talking about
then you would have assumed that he was not using proper terminology. Its a
bit too semantical to get hung up on a phrase of words that are so closely
related together.
Unless you didn't know what he was talking about to start with. Somehow I
find the latter of the two to be more probable. "What do you mean stress on
the driveline, thats dangerous!"
No shit sherlock. Congratulations for pointing out the obvious. :clap:
*EDIT*
In case you didn't read this.
"The driveshaft is inside a metal case that bolts to the engine which bolts
to the transaxle. This helps keep good balance and provides rigidity."
That SHOULD have cleared up any doubts you may have had.
DSMer
Don't try to answer for him. I wasn't being a stickler. He's talking
about a proposed new design.... not the old one.
I don't assume he's not using proper terminology. I assume he knows what
he's talking about, and I want to discuss it with him.
You make a "quote" that I didn't say, then say "no shit sherlock"
??:screwy:
You sure showed me not to make a point .... that I didn't make.
duh..... like i said, I knew exactly what he was talking about. But my
doubts are not with the OLD design. He was talking about a NEW design.
Extend your quote to read this (in case YOU didn't read it)
I'm not arguing what they DO do, because that would be kind of stupid.
Notice that he's proposing that they do something different?? I'm
discussing/debating HIS design, not the old C6 design.
windsonian
Ugh why do these threads degenerate so. The torque tube is part of the
drivetrain. I wrote driveline, sorry. I used incorrect terminology since I
interchanged the two although they probably are interchangeable, whatever).
Yes I do mean increase the rigidity through modification of drivetrian
components (such as the torque tube, obviously not the prop. shaft).
Basically make the drivetrain double back as more of a spine of the car. No
I haven't thought about all the details or the best way to do it. Yes I
realize minimal torsional gains are to be had. I think its a good idea
thats all. Whenever you can kill two birds with one stone you gain.
rudypoochris
ok ok....
so you want to keep the idea of a "shaft within a pipe".
So, as you understand it, the current design uses the "torque tube" for
stiffness / rigidity, but not for structural strength??
If you're using it as a structural "spine" of the car, the whole thing
would have to be suspended, would it not?
If so, then you'd have to either suspend the diff (or gearbox if it is in
fact in the rear also) and put a couple of CV's on the axles, or have a
break in the drive shaft just before the diff/GB.
I suspect you would go with the latter, which seems to be pretty much what
they're doing with it now.
I guess it sounds (in general) pretty much exactly what they're doing with
it now. If you're going to strengthen the spine, you just have to make
sure your 1 stone is killing your birds. Where can the weight then be
eliminated i guess? Is a structural member down the guts of the car the
best chassis design? Because if it's not, are we really making any gains
by using it that way? I understand you just want to give something 2 uses,
but if it's not the most efficient chassis solution, then are we just doing
it for the sake of it??
hmm.... a lot of questions .. not too many hard and fast answers yet.
Interesting concept though.
windsonian
:sleep:
The torque tube ALREADY acts as a main part of the Corvettes structure. The
rear end pushes on the torque tube, which in turn pushes on the engine
which is mounted to the subframe that is a part of the cars frame.
The structural rigidity of the frame is already taken care of with the
seamless tubes on the C6. Over engineering an already simple design won't
fix anything.
DSMer
why are you telling ME this?
windsonian
Because you wasted several bytes of valuable bandwidth trying to elaborate
and understand a theory that didn't need to be explained simply because it
was faulty in logic from the get go. That is WHY.
Because I can tell you anything I want to. WHY are you reading it? Thats
the more important question.
DSMer
Go easy. For the intelligent learned engineer you try to portray yourself
as, you sure do get into alot of petty disagreements. I know you think you
know everything, but the fact of the matter is that GM is already using it
as a structural member to an extent. Thus it is possible that by furthering
its importance as a structural member more weight may be saved or more
stiffness may be had, either results in the same goal. Obviously there are
limits. For instance maybe GM didn't go all out with it for cost reasons...
comes to mind immediately.
No, a torque tube is not necessarily the best, or even a very good design
at all for torsional rigidity. I was thinking more along the lines of a
webbed "torque tube" that would be less tubular in shape and more planar.
To it would be bolted the rest of the body. It would still be a unibody I
guess, but it does go a little bit back to the old "frame" idea. In this
case the spine as I have been calling it would be stressed. Basically the
engine would become a cross member, so would the torque tube, and the
transmission. Etc. Removing the drivetrain wouldn't make the car fall
apart, but it would be severly weakened to the point that you wouldn't want
to drive it at all if it did have an unstressed drivetrain in it.
These are just dreams of mine and penciled ideas though. I don't know if it
will actually work. Was just a thought. Sorry I didn't think it all the way
through or explain thoroughly.
rudypoochris
what about maybe your "tube" is not a single piece, so it could be made so
important as to be necessary for the car to "not fall apart". if it wasn't
a single piece, you could potentially still get the drivetrain out without
destroying the car.
Like you said, it doesnt need to be a tube as such. It's only there to
avoid having a bare rotating shaft (and for the afore-mentioned stiffness
etc)
windsonian
Trying to copy european design i see...gay!
newyorker
This is all a WASTE of time. Explain to me. How can a planar shape properly
house a circular tube giving it play equally in every direction? It can't.
Thats the simple answer. Don't try to justify YOUR bullshit logic AGAIN.
You can't even properly understand how a simple combustion works. What
makes you think I would take your word on complicated chassis design?
"Removing the drivetrain wouldn't make the car fall apart, but it would be
severely weakened to the point you wouldn't want to drive it"
Really? So I guess you have a car that drives without a drivetrain? Right..
and I suppose you also drive a hovercraft. F*cking pitiful. Just stop now.
Please..
Of course I think I know everything. I was here before the creation of
human life and I'll be here long after all of you are gone. I've accepted
this FACT. Why can't you? Congratulations you've discovered the truth of
life. :clap:
DSMer
Wrong question champ. It doesn't need "equal play" in all directions, it
needs sufficient play in all directions. Which is completely feasible.
We're talking about the structure, not the transmission.... wow.
They not bother with reading comprehension for $30k?
windsonian
I think all you nerds are missing the point.
......................
If Chevrolet does this and keeps the Corvette affordable and "pretty", this
will be an amazing image manuever for the Corvette. If the mid-engine
design is successful and they keep improving the interior quality AND they
maintain a good bang for buck...why buy a Ferrari? Well I understand the
reasoning for buying a Ferrari but *this* Vette could make Ferrari/Lambo
buyers think. 400+hp...mid-engined...decent interior...excellent
performance...what will the Europeans bitch about?
If only GM worked so hard on its other cars like they do with their
Corvette.
.......
Go ahead nerd posters...continue explaining engineering shit you don't
really know.
What
Wonder if this next corvette will have a cheap interior and leaf springs
too :banghead: goddamn GM needs to get their head out of their ass
newyorker
Apparently the leaf springs are working and at an affordable price. Let me
guess you want a way better interior, and better suspension pieces all
around and better this and better that. Okay then it will be the price of a
ferrrari.
This is supposed to be a bargain priced supercar that why it uses some of
the things it does.
Enthusiast
The corvette is a super car, but nowhere close to being a supercar. Using a
non leaf suspension and better interior will not up the price of the car
120,000 dollars to put it in f430 territory...everything else on the
corvette is fine its a great performer but for me the leaf springs are
stone age, and honestly my civic uses a higher quality material for the
interior than the vette. Not talking seats or head up display w.e it is,
but just the dash I think mine would be worth more in scrap parts. If I was
looking at a plastic car, id get an evo that performs just as well, handles
better, uses modern technology, and is 1/2 of the cost of a vette
That or id get some Mattel toys..they probbably have less recalls than the
corvette will also
newyorker
The interior really isn't that bad at all. It is ALOT better than even a
new civics interior. Maybe you should try driving a C6. Yes, it has leather
or atleast something close to it. Last time I checked the civic didn't. I
wouldn't call the Z06 a supercar though. It does perform as one, but it
isn't rare enough.
The fact of the matter is that those stone age leaf springs work. They are
light weight an effective. Are you suggesting that by switching to coils
which place more weight higher up there would be some sort of performance
gain? The rear suspension is still fully independant with the
monoleaf...
As for my idea being completely retarded and such regarding the use of the
driveline as a structural member... Okay, I guess. They already do this to
an extent though so I am not sure how you can complain that it wouldn't
work... thats okay though, I didn't expect you to really be open to new
ideas after your gross display of "knowledge" regarding the EFI system.
rudypoochris
Fact of the matter is its underengineered...I would never pay 60k for
something that uses 25 year old technology in something as vital as the
suspension.
newyorker
Pure ignorance.
I don't think you even know what a leaf spring is. What's wrong with the
design? Where is it located? You'll struggle to answer these questions.
Stop listening to Jeremy Clarkson or other anti-Americans hating on the
Vette and go drive it yourself.
The C6 Corvette interior is excellent. It isn't Audi good, but it's better
or on par with Boxsters and Lotus. Have you sat in one?
Evos are good, but I'd rather the FASTER, more refined, smoother riding,
more powerful Corvette. Get real. These aren't the same leaf springs from
25 years ago, don't be ignorant. How old is the combustion engine?
What
This has been gone over before. It resulted in ChrisV saying pretty much
what 'What' said earlier, just more in depth and some very valid (and
technical) points were raised. I do tend to agree with you though, leaf
springs are stone age, even buses don't use them anymore! :banghead:
It's all too easy to blame Jeremy Clarkson for why people think leaf spring
suspension is old and past it, but that's the way it is. Old. And tired.
Cliffy
On par with lotus! hahahah the elise doesnt even have carpeting I believe
its all plasticy and lightweight. A leaf spring is this...I dont see it on
SUVs anymore
http://www.eng.wayne.edu/legacy/images/AEImages/Leaf_spring.gif
Yes I have sat in a vette and it was crap. the only thing I liked were the
seats and HUD thats all. A vette cant touch an evo on the track at the
strip sure, but dragstrips dont really involve too much driving skill. Its
stoneage, I dont care if they are from 25 years ago or not. My ****ing
civic has a more advanced suspension for ****s sake
newyorker
Nurburing Lap Times
7:43 --- 2006 Corvette Z06
7:56 --- Chevrolet Corvette Base C6
8:11 --- Mitsubishi Lancer EVO IX
Reality sucks.
Laps on the Nurburing can vary from driver to driver, but seriously, the
Evo machine appears to be at a disadvantage.
The new Evo will probably be slower.
What
This post is so full of bull shit its retarded.
Im willing to bet a Vette could outrun an evo on most road courses.
And I get so tired of people saying driving at the strip is easy. Your not
allowed to say that until after you cut some sub 2 second 60' times on
street tires and over 300whp. You probably couldnt run a 14 in a c6.
Have you looked at your civics suspension. haha
Everytime we have one on the lift at work we all come and look at all the
shitty looking parts and laugh. Yah your right your civic has such good
suspension.
And I have a road and track sittin next to me so we are gonna go to that so
I dont have to look anythign up.
skidpad slalom
Corvette Coupe non Z51 .95 67 mph
Evo .88 68.9mph
So looks like the vette has more grip but the evo is slightly more nimble.
Id be willing to bet the vette would run just a good through the corners
and then power away from the evo on the straights.
Enthusiast
Uhhh a Z06 will eat an Evo alive. Strip or road course. Even at the AutoX.
It has alot more contact patch and it weighs less.
As for the corvette leaf spring... Your logic clearly shows why you own a
civic and not a corvette. No offense...
The Corvette leaf spring which is oh so antiquated is actually made of
composite. It weighs less than the coils it replaces, it is placed lower in
the chassis, it outlast the coil spring, and you can adjust the ride height
of the vehicle based soley off the end links with out changing springs.
Fact of the matter is that it works, and damn well. It works BETTER than
the coil springs it replaced.
Also, please realize the C6 Z06 actually ran a faster lap than the McLaren
F1 around the Nuremburg ring. The Evo flat out didn't. Enough said on that
Evo v. Corvette debate.
Road and track got this for slalom and skid pad, C6 on the left, Z06 on the
right:
200-ft skidpad 0.93g 0.96g
700-ft slalom 69.9 mph 71.2 mph
Corvette is more nimble than the Evo, as I said, weighs less, has more
power, and more tire.
rudypoochris
While that may all be true, and I might have been wrong, I still wouldnt
buy one..i just dont like american cars plain and simple..I think I could
have just as much fun in an NSX
newyorker
While thats great for you. I don't think your Chevrolets target audience.
Can you afford said NSX or Corvette? If not I doubt Chevrolet cares too
much unless your friends looking for super cars really listen to everything
you say. In any case, as I was saying, while all that is your opinion, it
doesn't change the fact that lots of people prefer the better performance
and lower cost of a Z06 to an NSX, hence why Corvettes outsell NSX's.
rudypoochris
Thats not the only reason. A corvette is an icon, and a name, while an NSX
is still a honda. Sure you can get used ones for as little as 25-30k, but
still, an NSX is a honda and a corvette is a corvette, it has history
behind it
newyorker
Stop the madness. "Just" a Honda? Thats what you believe people think of
the NSX?
The NSX name is legendary. It changedFerrari. People who know cars know
that the NSX was arguably the best supercar of its era. People who don't
know cars won't recognize it as a Honda vehicle.
Honda was asking potential NSX customers to pay the price of a very good
modern sports car for a car that hasn't been new since 1991...and yes, it
still has less than 300hp. A 350z might out perform it, all of today's M
cars will, but a Z06 would straight up stomp that mutha f'er. Today"s
Corvette is way more powerful, more advanced and cheaper than the NSX.
Aside from being in different price brackets, these are the reasons
Corvettes out-sell NSX. Stick a Honda excuse up your ass.
What
I've asked you this befor,e but does it physically hurt to be this closed
minded? Yore' a retard, pure and simple You don't even know the rudimentary
facts behind the vette's composite "leaf" spring and why it works so
well.
To repeat what I posted before...
1st... the Corvette uses an extremely lightweight composite monoleaf that
is about as high tech as suspension components get. By mounting it on the
car in the center of the "leaf," the spring actually carries it's own
weight, which is better for suspension response. It weights A LOT LESS than
coil springs. One leaf replaces two coils. The two coil springs weigh 3
times as much as the one leaf. Additionally the leaf is placed at the
bottom of the car so that in addition to removing weight you lower the
CG.
2nd...traditional buggy leave springs were multi leaves and were used as
suspension arms as well as springs, which was bad due to being inherently
flexible. Plus they had friction as the leaves rubbed against each other.
The Corvette's monoleaf only has olne job to do: be a spring. That's what
makes it unlike any other leaf spring suspension of old cars.
3rd... you really think coil springs are some sort of new development?
Why doesn't everyone use it?
-Engineers like to stick with what they know. Lots of suspension engineers
are familiar with using coil springs. They could experiment with leaves if
they wanted or they could stick with coils and get the job done.
-Perception. Just like pushrods, the leaf spring as a stigma attached to
it. The reasons for the stigma are legit (a key component to old, heavy and
typically poor handling suspension). However the reality is the sum of the
older parts was the problem, not a specific part of it. In the older buggy
spring type setups (like the rears of older cars) the leaf spring was not
just the spring, but all of the suspension. The Corvette is actually a dual
A arm suspension that has one half of a high tech composite leaf as the
spring, and that's all the leaf does.
Coil race springs are not car specific. You select rates, diameters, length
etc but you don’t have a specific spring for a specific car. If you want to
order a custom spring Hypercoil will wind it to your specifications on the
same machine they use for the next custom spring. A custom Porsche, Formula
Ford and LMP car spring can all be made on the same machine. By the time
the C6 evolves into a C6-R (they don’t start off with a production
Corvette) the suspension geometry is so different that they couldn’t just
mount a C6 leaf spring. It’s far too expensive to have a few custom leaf
springs tooled up (you would have to buy the tooling as well as the
springs) so they use readily available coil springs.
This type of universal tooling isn’t available for the composite leaf
spring. Only the Vette currently uses the spring so you are making a Vette
only part. This seriously reduces the market for aftermarket composite leaf
springs (still there are after market leaf springs available for the
Vette). The business case for custom equipment to make Vette springs is
harder to justify since it’s a smaller market.
In reviews, such as between the Corvette and say, Porsche, the reviewers
are using the stigma as fact. They still equate the leaf with old style
buggy leaf suspension and look for reasons to call it out, even if they
have to make up those reasons. The differences in the car's "feel" have
nothing to do with the spring material, but with shock/spring rates and
with car layout (the Porsche is heavily rear biased, the Corvette is evenly
balanced, but heavy). But since the dual A arms of the Corvette have a
single composite monoleaf half attached to it at the outer end, those
reviewers think that the "stoneage leaf spring suspension" is sub par in
comparison,and to blame for the differences in feel. It could be tires and
tire pressures. It could be in alignment specs, or A arm geometry, or in
the bushings in the steering. Assuming it's the composite monoleaf because
you equate it with old style buggy springs is ludicrous, but magazine
reviewers will do that. And so did you.
Ignorance colors your perception of the world and you think it's perfectly
acceptable to BE ignorant and idiotic.
ChrisV
