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  • Curb weight guesses?

    Like many, I am very interested in what the weight of the new car will be. Have seen a few posts saying it will be heavier than a C7, but without supporting arguments. There are many members here with engineering and racing experience. So what do you all think?

    Here’s my estimate: Start with a C6 ZO6 with all the luxury options. Figure 3,200 pounds. Subtract 200 pounds for shorter exhaust and eliminated torque tube assembly. Add back 200 pounds for newer electronics and additional safety equipment. So, I’m back to 3,200 pounds for the non supercharged base C8 ME production car.

    An over/under guessing survey with mean and standard deviation statistics would be great fun.

  • #2
    GM has been lately removing 200 to 400+ pounds from their SUV’s and pickups, though that is much easier to do. Its relatively lighweighting program is impressive. I hope you are right AbqVic and that it is 3,200 pounds, but my guess is maybe 75 more than that.

    Comment


    • #3

      2999 Lbs.

      A lay guess. The will, desire and pride of the build team will determie the weight . Not what is easy but what is possible will define.
      The C8 team intends to match the state of the art, now about 3000 as to weight. Has the desire, will, opportunity and resource, it can be done. So, they will probably succeed in at least one variant of the C8.

      Right. Curb with fluids. Remember the C5 Z6 at 3118 Lbs 18 years ago. Less stuff then. Lighter stuff now. Its a wash.



      2002 Chevrolet Corvette Z06 AARON ROBINSON
      AUG 1, 2001[IMG]https://hips.hearstapps.com/amv-prod-cad-assets.s3.amazonaws.com/images/01q3/267338/2002-chevrolet-corvette-z06-road-test-review-car-and-driver-photo-9746-s-original.jpg?fill=2:1&resize=480:*[/IMG]
      Let's call it the Corvette 5.5, as the 2002 405-horsepower Z06 is the fifth opportunity in five years to unload valuable pesos on the latest and greatest Corvette. If you own a Corvette "5.4," the 2001 385-horse Z06, it is now on a depreciation schedule akin to that of an IBM Selectric. Asked why GM would sell 7400 vehicles knowing they would be obsolete within 14 months, Corvette chief engineer Dave Hill said the 5.5's upgrades weren't ready then and that the company doesn't sell wine before its time. Hope that helps . . . Just as the Corvette 5.4 was when it was introduced last year, the Corvette 5.5 is faster, with more installed technology. It will also cost more when it hits stores at the end of the summer, although exactly how much more GM has not said as of this writing.

      The 5.5 is expected to cost $1000 to $2000 more than the Corvette 5.4, which has a base price of $49,128. Thus, the 5.5 will be the most expensive stock Corvette in circulation. The biggest change 5.5 users will notice is the revised LS6 V-8, whose output has risen by 20 horsepower to 405 at 6000 rpm and by 15 pound-feet of torque to 400 at 4800 rpm. Almost all the added power is at 3500 or higher rpm, while the redline remains unchanged at 6500 rpm. About half the horsepower increase comes from a lumpier camshaft that pushes intake-valve lift by 0.7 millimeter to 14mm and exhaust lift by 0.5mm to 13.9mm.

      To handle the change, assistant chief engineer John Juriga and his crew added fortified valve springs and lightweight hollow-stem valves, a feature last seen on a Corvette in the late ZR-1's twin-cam LT5 V-8. The valve stems are drilled with walls just 0.8mm thick, topped up with a sodium-potassium mix that helps dissipate heat, and then spun at high revolutions to friction-weld a cap on. At about $8 apiece, they are five times the price of the old solid-stem valves. Otherwise, Juriga and company left the LS6's cylinder heads alone, making changes upstream and downstream to eke out small improvements. A redesigned filter box in the nose flows more air more smoothly, allowing engineers to dispense with the mass airflow meter's honeycomb "air straightening" screen.

      All of that is worth about five stallions, while another five come from removing the two small manifold catalysts that helped the Corvette 5.4 pass federal smog tests. Juriga says the precatalysts, worth 5.5 pounds and an inch of mercury each in back pressure, aren't needed to meet the standards now that redesigned underfloor catalysts are in place. The Corvette 5.4's fabulous titanium mufflers remain standard equipment. Gracing the front axle is a thicker anti-roll bar with aluminum links. The curb-to-curb turning circle shrinks by 2.1 feet to 40.2. The rear shocks are recalibrated to provide more compliance over corrugated pavement but slightly more resistance to low-frequency motion such as acceleration squat and transitional body roll.

      The Corvette 5.5 also rides on new spin-cast alloy wheels from Speedline, replacing last year's identically styled forged units. Sadly, magnesium wheels are no longer an option on any Corvette. GM claims a 12-pound decrease in the Z06's curb weight to 3118 pounds, in part due to the lighter Speedline wheels. The head-up display, not available on the Corvette 5.4, is standard on the 5.5. So is a CD player. Dark Bowling Green Metallic, last year's least popular color and only available on Corvettes 5.1 and 5.2, is gone, replaced by the Electron Blue, which will be available on all versions.
      ----------------------------------------------- end of article



      The C6 Z06 was about the same weight as the C5. The C7 was an aberration at 3400 Lbs . So. 2999 should be attainable, relatively. The Tech for lightness is on the front burner and progressing the last 25 years.

      7,576 viewsJun 1, 2016, 09:15amHow GM Is Lightweighting Its Cars With Advanced Manufacturing Technology


      Karl BrauerKarl Brauer
      Contributor
      AutosI am the Executive Publisher at Autotrader and Kelley Blue Book

      Photo courtesy of General Motors

      General Motors GM +0.11% is operating full steam ahead when it comes to integrating lightweight materials and innovative manufacturing techniques into its new passenger cars and trucks. That was the takeaway after Kelley Blue Book's recent visit to the iconic GM Design Dome at its Warren Tech Center outside Detroit, Michigan. During the tour, the giant metallic silver dome ― that has served as a private evaluation hall for virtually every vehicle GM has built since the 1956 model year ― was chock-full of exhibits intended to demonstrate and preview the company’s lightweight innovation.

      Steel, more specifically low-carbon steel, has been the standard building material for cars and light trucks for more than a century. In truth, the commonplace material is an excellent choice as it is relatively inexpensive, easy to weld, simple to bend into shape, and it has good resistance to fatigue. It’s drawbacks, however, include a relatively limited resistance to corrosion and weight ― it is heavy. Paint and galvanizing have nearly eliminated its first negatives, but it’s physically impossible to reduce the mass of low-carbon steel.

      Photo courtesy of General Motors





      Traditionally speaking, weight hasn’t been a significant concern when it comes to passenger vehicles as automakers have always focused their attention on making occupants comfortable, simply adding horsepower to offset increased mass. Yet more stringent fuel efficiency regulations, and the realization that lighter vehicles deliver better performance, have all of the world’s car and truck manufacturers looking very hard at "lightweighting" — an auto industry term that refers to the process of building vehicles that are lighter an effort to improve economy and performance.

      As I learned inside the Design Dome, General Motors is taking a multipronged approach to tackling lightweighting. These include introducing new assembly materials and challenging its engineering team to come up with new innovative approaches to vehicle construction. YOU MAY ALSO LIKE




      Photo courtesy of General Motors

      Aluminum alloy is near the top of GM’s lightweighting list. The same basic material used to make commercial aircraft is the new material of choice for most automakers as the metal is lightweight, easy to work with, durable, and more corrosion resistant than low-carbon steel. But it isn’t all good news with aluminum, as the material costs more, requires expensive tooling, and it is more difficult to assemble especially when it is being attached to another dissimilar material. GM has chosen select applications for the alloy, using sheet aluminum for body panels, extruded aluminum for frame rails, and intricate aluminum castings to replace parts that used to require dozens of small pieces to be assembled into one large unit — this saves weight, reduces complexity, advances stiffness, and improves crash performance. Aluminum is used extensively in the Chevrolet C7 Corvette and the Chevrolet Malibu (the new Cadillac CT6 uses so much of the lightweight alloy to replace low-carbon steel that its full-size luxury sedan weighs less than a BMW 5 Series).

      In some cases, aluminum alone isn’t the best material. High-strength steel — an alloy that has been formulated to meet specific mechanical properties — accompanies the lightweight alloy to add strength, corrosion resistance, and sound absorbing properties. These materials have different mechanical properties, which has forced the company’s engineers to develop techniques to adhere aluminum to steel.

      Photo courtesy of General Motors

      One solution is with advanced spot welding. Special techniques were created by GM’s engineering team that allows materials with different melting points to be bonded together. The automaker is able to combine a lightweight aluminum skin (e.g., a hood or trunk lid) with a sturdy steel frame, which allows each material to complement the other’s strengths while reducing overall weight (GM expects to license many of its technologies to other automakers).

      Parts often need a more cohesive mating to make the bond stronger, which is where welding comes into place. While fusing similar metals is a simple task, welding aluminum and steel together is difficult because aluminum melts around 1,200° F. while steel melts at 2,600° F. Despite this challenge, GM is credited with engineering special techniques and processes that allows them to fuse materials with different mechanical properties together without destroying one or the other. Taking this technology one step further, the company’s engineers have developed a welding tip that is able to accommodate aluminum-to-aluminum, steel-to-aluminum, and steel-to-steel welding, which greatly speeds up the assembly process. As an added benefit, multi-material welding eliminates the need for heavy, and costly, rivets — GM can save upwards of $100 per vehicle simply by eliminating rivets.

      Photo courtesy of General Motors

      Aluminum and high-strength steel aren’t the only metals GM is exploring, as the automaker is also using magnesium in vehicle construction. Magnesium is one of the lightest of all metals — 33 percent lighter than aluminum — boasting both strength and a resistance to corrosion. It is easy to cast and machine, and its lower working temperatures extend the life of the equipment used to produce the parts. Unfortunately, magnesium has a lower melting temperature than most other metals and it isn’t particularly strong (compared to steel), which does limit some of its applications. Nevertheless, it is an excellent structural material for large castings and specific parts. GM is currently experimenting with magnesium panels for doors and trunks (the automaker has developed corrosion-resistant coatings to ensure its magnesium sheet metal lasts the life of the vehicle).

      Carbon-fiber is one of the most promising lightweight automotive construction materials. Five times as strong as steel, twice as stiff, yet only a fraction of the weight, the non-metallic substance may be woven, formed, and molded into nearly any shape. Carbon-fiber is extremely strong and highly resistant to corrosion, yet it is not as heat resistant as most metals (primarily because of the resin that holds the fibers together). Racing teams and aircraft manufacturers have been praising the benefits of carbon-fiber for decades, but the material was always deemed too expensive for mass produced vehicles. Not anymore, as GM is working on a carbon-fiber wheel program that promises to drop vehicle weight by upwards of 40 pounds — wheel weight is considered “rotating and unsprung mass,” meaning every ounce shed makes a big improvement in efficiency and driving dynamics.
      Last edited by SheepDog; 03-16-2019, 09:27 PM.

      Comment


      • #4
        GM has never been able to produce a truly lightweight car (Corvette or otherwise, at least compared to the competition), so I am guessing the C8 will be no different. I figure 3300-3400 pounds depending on configuration. Still slightly lighter than the C7 and about the same as the C4. Would really like 3000 pounds but ... !

        Comment


        • #5
          If the frame is going to be designed to handle up to 1000 horsepower, be comparable with future AWD and even hybrid, its not getting any lighter.

          Comment


          • #6
            Thank you SheepDog. Very interesting reading. There is another component of GM’s lightweighting program that I have posted several times earlier so it will be familiar to many. It offers a fascinatring way to reduce weight, add strength, and reduce the number for component parts all at the same time.

            This 2:07 video is my personal pick as the best ME video of all I have seen:

            https://video.marketing.gm.com/10508...-weighting.mp4


            GBA Black; HTO Twilight/Tension interior; Z51 & Mag Ride; E60 lift; 5VM visible carbon fiber package; 5ZZ high wing; FA5 interior vis CF; ZZ3 engine appearance; 3LT; Q8T Spectra Gray Tridents; J6N Edge Red Calipers; SNG Edge Red Hashmarks; VQK Splash Guards; RCC Edge Red engine cover; VJR illuminated sill plates. Lifetime, annual contributors, and 23 year members of National Corvette Museum. Home is the beautiful Pacific Northwest.

            Comment


            • #7
              so my guess is 3400 lbs which i believe to be wishful thinking. the OP thinks the C7 Z06 weighs 3200, which is not correct unless that was for a stripper that was never produced. mine says 3576 in the door jam sticker. it is a 3lz which is about 70 lb heavier than a 1lz, is a Z07 with carbon brakes about 40 lbs less. in looking at other club members C7 Z06's, i found the range from 3420 to 3590, with a mix of M7, A8, 1Lz, 2Lz and 3Lz.

              even at 3400 curb, the C8 would represent about 150 lbs lighter than the C7 Z06. maybe the base model at 3200 is a possibility.

              also, the article on GM lightening is 3 years old so they have been working on weight reductions for awhile. trouble is, frame and body weights get reduced less than the added weight of new features.

              GM would have to make a major departure to get the weight of the C8 close to the 3200 lbs of the C6 Z06.

              Comment


              • #8
                Both Sheepdog and John; thanks for the lightweighting information. I had completely forgot about the program when I made my 3,200 pound estimate.

                I really admire the Corvette design team’s abilities, so I’ll be optimistic and join Sheepdog by also estimating 2,999 pounds.

                Comment


                • #9
                  IDK. Every new Corvette has been creeping up in weight for some time. I would like to find they have succeeded in keeping the weight down.
                  If I could, I’d like to see it come in at 3000lbs.

                  Comment


                  • #10
                    While we care about every pound, as does GM, there used to certain ‘weight classes” that related to government fuel standards. I remember that the C5 came without any floor mats. When I asked Dave Hill (Chief Engineer then) as to why, is that he said that without floor mats, the car’s weight met some car classification, but with the floor mat, it exceeded a particular one by one pound. Hence they decided no standard floor mats that year.

                    Dave also had a standard he constantly repeated to his C5 development team, that if you can cut one pound from the car, we can spend up to $10 more in better grade materials. Dave of course was the wonderful task master when it came to weight, and why the C6 Z06 with its 427 ci motor, came in at 3,130 pounds.

                    All this info by why of my wondering out loud if those weight classes still exist (anyone know?), and if so, GM of course would try to meet one of those.

                    Hence my wild guess is that it might weigh 3,249 pounds.
                    GBA Black; HTO Twilight/Tension interior; Z51 & Mag Ride; E60 lift; 5VM visible carbon fiber package; 5ZZ high wing; FA5 interior vis CF; ZZ3 engine appearance; 3LT; Q8T Spectra Gray Tridents; J6N Edge Red Calipers; SNG Edge Red Hashmarks; VQK Splash Guards; RCC Edge Red engine cover; VJR illuminated sill plates. Lifetime, annual contributors, and 23 year members of National Corvette Museum. Home is the beautiful Pacific Northwest.

                    Comment


                    • #11
                      I’ll throw out my guess! I would love to see 3k however I don’t see it as realistic. It’s not that they can’t is simply to costly to get there. How many ME cars weigh less than 3300 and then factor in the ones that have at least 8 cylinders! Now factor in the required/added safety equipment. My guess is 3300-3350, anything less and I’d be significantly impressed. However I think the Z06/further performance cars will be benfited by not needing as much cooling and I think they’ll leave room to reduce weight on those cars. So hopefully the FI cars only gain 40-75 lbs not the 150 or so that we are currently seeing. Also not im quoting “as tested” not this ridiculous dry weight thing that Europeans like to quote!!

                      Comment


                      • #12
                        The McLaren are setting the standard as to weight lightness in production cars. 1. The weight goes down as the price goes. 2. The weight goes down as time goes. The least expensive is the heaviest, the 570 S, ‎1440-1484 kg (3175-3272 lbs).


                        2017 Ford GT [ from Google]
                        The Ford GT, with the "carbon fiber everything is
                        CURB WEIGHT 3,050 lb {or dry???]
                        ---------------------------------------------------------
                        2017 Ford GT from From Wikipedia: $400K$ Lightness and a great product
                        106.7 in (2,710 mm)
                        187.5 in (4,762 mm)
                        78.9 in (2,004 mm)
                        43.7 in (1,110 mm)
                        3,354 lb (1,521 kg)[17]
                        So, How much lightness will 70K$ buy in a new C8 Mid-engine Corvette. ???

                        2999 Lbs because they have something to prove that they can do it. Optimistic.



                        McLaren 12C
                        McLaren 12C Spider Specification. ... VEHICLE DYNAMICS ... DRY WEIGHT, 3,033LB. DRY WEIGHT*, 2,956LB.

                        650

                        The 650s Spider utilizes the same carbon-fiber MonoCell chassis underpinning the coupe and doesn’t require any reinforcing or structural strengthening with its top removed. McLaren says the Spider will have identical ride and handling characteristics with no noticeable losses in performance. And even with the addition two-piece mechanical top, only 88 pounds is added to the 650S’ 2,932-pound curb weight, bringing the Spider’s dry weight to a sill-respectable 3,020 pounds.



                        675 LT
                        Specification of the McLaren 675LT the lightest, most driver-focused, most exclusive ... DRY WEIGHT, 1,230KG.

                        570 S : Least expensive is the heaviest.
                        2016 McLaren 570S specs, specifications, laptimes, acceleration times, pictures, photos, engine data, top speed.
                        Curb weight‎: ‎1440-1484 kg (3175-3272 lbs)




                        720S
                        The interior of the car includes a folding driver display and carbon fibre accents. The McLaren 720S weighs just 1,283 kg (2,829 lb) dry, making it the lightest in its class.
                        Kerb weight‎: ‎1,437 kg (3,167 lb)
                        Power output‎: ‎530 kW (720 PS; 710 hp)
                        Engine‎: ‎4.0 L M840T twin-turbocharged V8


                        Senna
                        2,641 pounds
                        789 horsepower and 590 pound-feet of torque



                        600 LT
                        Jun 28, 2018 - McLaren is introducing the new 600 Longtail, a hardcore 570S with 592 horsepower and a curb weight lowered by 211.6 pounds compared to the standard model. ... extended by 2.9 inches (7.3 centimeters) compared to the donor car. ... and enable a remarkable dry weight of just 2,749.2 lbs (1,247 kg).


                        --------------------------

                        FORD GT:

                        2017 Ford GT from From Wikipedia:
                        106.7 in (2,710 mm)
                        187.5 in (4,762 mm)
                        78.9 in (2,004 mm)
                        43.7 in (1,110 mm)
                        3,354 lb (1,521 kg)[17]

                        ANOTHER VIEW:
                        With a dry weight of 3054 lbs., the Ford GT's power-to-weight ratio lands somewhere between the McLaren 675LT and the Ferrari 488GTB.
                        BY BOB SOROKANICH
                        JAN 25, 2017
                        Last edited by SheepDog; 03-17-2019, 04:15 PM.

                        Comment


                        • #13
                          And if it wasn't for the USSR dumping all their ex-submarine titanium on the world market at fire sale prices, and GM using it for the exhaust, they wouldn’t have gotten it down quite so low.

                          Comment


                          • #14
                            Just
                            Originally posted by SheepDog View Post
                            The McLaren are setting the standard as to weight lightness in production cars. 1. The weight goes down as the price goes. 2. The weight goes down as time goes. The least expensive is the heaviest, the 570 S, ‎1440-1484 kg (3175-3272 lbs).


                            2017 Ford GT [ from Google]
                            The Ford GT, with the "carbon fiber everything is
                            CURB WEIGHT 3,050 lb {or dry???]
                            ---------------------------------------------------------
                            2017 Ford GT from From Wikipedia: $400K$ Lightness and a great product
                            106.7 in (2,710 mm)
                            187.5 in (4,762 mm)
                            78.9 in (2,004 mm)
                            43.7 in (1,110 mm)
                            3,354 lb (1,521 kg)[17]
                            So, How much lightness will 70K$ buy in a new C8 Mid-engine Corvette. ???

                            2999 Lbs because they have something to prove that they can do it. Optimistic.



                            McLaren 12C
                            McLaren 12C Spider Specification. ... VEHICLE DYNAMICS ... DRY WEIGHT, 3,033LB. DRY WEIGHT*, 2,956LB.

                            650

                            The 650s Spider utilizes the same carbon-fiber MonoCell chassis underpinning the coupe and doesn’t require any reinforcing or structural strengthening with its top removed. McLaren says the Spider will have identical ride and handling characteristics with no noticeable losses in performance. And even with the addition two-piece mechanical top, only 88 pounds is added to the 650S’ 2,932-pound curb weight, bringing the Spider’s dry weight to a sill-respectable 3,020 pounds.



                            675 LT
                            Specification of the McLaren 675LT the lightest, most driver-focused, most exclusive ... DRY WEIGHT, 1,230KG.

                            570 S : Least expensive is the heaviest.
                            2016 McLaren 570S specs, specifications, laptimes, acceleration times, pictures, photos, engine data, top speed.
                            Curb weight‎: ‎1440-1484 kg (3175-3272 lbs)




                            720S
                            The interior of the car includes a folding driver display and carbon fibre accents. The McLaren 720S weighs just 1,283 kg (2,829 lb) dry, making it the lightest in its class.
                            Kerb weight‎: ‎1,437 kg (3,167 lb)
                            Power output‎: ‎530 kW (720 PS; 710 hp)
                            Engine‎: ‎4.0 L M840T twin-turbocharged V8


                            Senna
                            2,641 pounds
                            789 horsepower and 590 pound-feet of torque



                            600 LT
                            Jun 28, 2018 - McLaren is introducing the new 600 Longtail, a hardcore 570S with 592 horsepower and a curb weight lowered by 211.6 pounds compared to the standard model. ... extended by 2.9 inches (7.3 centimeters) compared to the donor car. ... and enable a remarkable dry weight of just 2,749.2 lbs (1,247 kg).


                            --------------------------

                            FORD GT:

                            2017 Ford GT from From Wikipedia:
                            106.7 in (2,710 mm)
                            187.5 in (4,762 mm)
                            78.9 in (2,004 mm)
                            43.7 in (1,110 mm)
                            3,354 lb (1,521 kg)[17]

                            ANOTHER VIEW:
                            With a dry weight of 3054 lbs., the Ford GT's power-to-weight ratio lands somewhere between the McLaren 675LT and the Ferrari 488GTB.
                            BY BOB SOROKANICH
                            JAN 25, 2017

                            All Mclarens cars use Carbon monocoque chassis which is how they get the weight down like they do. Ford Gt uses massive Caf and also a CF monocoque. I believe the 488 pista is around 3200 but the prices are so high because they make most of the panels with CF. GM can’t just cut weight because they have something to prove they still have a budget to work around and carbon fiber is very labor intensive.

                            Comment


                            • #15
                              Originally posted by TtiME View Post
                              Just


                              All Mclarens cars use Carbon monocoque chassis which is how they get the weight down like they do. Ford Gt uses massive Caf and also a CF monocoque. I believe the 488 pista is around 3200 but the prices are so high because they make most of the panels with CF. GM can’t just cut weight because they have something to prove they still have a budget to work around and carbon fiber is very labor intensive.
                              Yes. True, Time. But some versions of the C7 Stingray were within spitting distance of the curb weight of the Ford GT and about close even with the 488 and 570S curb weight, even with the C7's "economy" construction material. The C7 is an "old" 2013 design. The C8 folk have had 6 years to work and 6 years of general tech advance in the industry, since the C7 design was set in stone. Therefore, it is there for them if they want it, weight target.



                              The Corvette C7 Stingray Curb weight was:
                              4,492 mm (177″)
                              1,877 mm (74″)
                              1,239 mm (49″)
                              2,710 mm (107″)
                              1,600 mm (63″)
                              1,568 mm (62″)
                              1,495 kg (3,296 lb)
                              49% - 51%
                              The C7 Z06 and ZR1had some extra ballast on board to make that FE car stronger to keep up with the supercar MEs. The C8 heavy hitters will [may] pack smaller lighter power plants and associated hardware. All guess work. All guess. But they must work for it and they have taken the time, plenty time to get something[?] right. So why not? A lot of it comes down to will and desire, all over life. Detroit and Bollingreen too.
                              Last edited by SheepDog; 03-17-2019, 06:43 PM.

                              Comment

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