Not a problem as I said in my previous post.

I would not say its available to the general public, you could apply for a vehicle, they are all built to order... people can be approved of buying the car, but not just anybody with say 40k-80k can just go out and buy one. Maybe make a driving test mandatory or something. Did I say 600hp? I might have, but I was thinking more along the lines of an LS6 with full exhaust and intake.

 

An opel speedster (close to Miata size) could meet this weight provided the ls6 could fit in the engine bay (dont know if it would). A fiero with an aluminum chassis may be about 200lbs heavier, since airbags would increase its weight. I have seen it printed in articles about fiero's that GM's own engineers stated that a mid-engine design could handle almost unlimited horsepower. They also have excellent launch capability-it would be hard to spin the wheels.

 

Yeah, but the only problem I see with the Speedster is that it is still a very small car, very lightweight mind you, but I don't know how its chassis could handle great deals of torque without some bracing involved.

If you have GT3, take a Speedster, reduce its weight and add all the goodies, it runs laps only about 4 second's slower around Laguna than my 1000+hp Panoz.

 

You confuse me.

You start off talking about a 2200 pound $40,000 car, now you are talking about $80,000, and are using as examples, cars that sell at cardiac arrest prices! Let us know when you are changing the rules in the event we want to also play, okay? Ferraris, Saleen S7s, FFR Cobras, and your other examples aren't exactly in the realm of our initial discussion, is it?

(Yes I looked up Ultima GTR, but I did not believe you were bringing in a $90,000 car to bolster your point for a $40,000 one! Depending on one's view, I either over or underestimated you in this area. Sorry.... )

In case you haven't noticed, this isn't exactly a website of millionair stockbrokers or born wealthy rich kids here. Most all of us won't ever buy anything more expensive than a Corvette, and the majority of us will be socking away till we are well into our 40s or more just to do that.

So while I'm carving "Stamped steel cars are heavier" onto my chest (right next to "Carbon fiber cars are more expensive" and "Paper thin bodies last about 10 minutes in the outside world"), I will ponder why none of the world's automakers who actually produce cars that people actually buy in quanities that's actually not going to gaurantee bankruptcy don't jump on this carbon fiber bandwagon, or hire Riley-Scott to do their chassis work.

On 2nd thought, perhaps it's because these cars are special purpose cars. Maybe, the only way for these cars to be done profitably is to sell them at the prices they are going for. In racing, the main objective is to make as light of a car as possible. There's no federal regulations regarding crash standards, and the buyers can afford them. Perhaps there's a reason why a $45,000 Corvette isn't built this way. Perhaps there is a reason why the street versions of all the cars you mentioned costs so much. Perhaps, we aren't even talking about $40,000 cars anymore, because no one is making a car like this, and selling it to the public at $40,000! Whoa......Imagine that.

This all brings us back to your initial proposition and my point throughout this, which Z28wilson (and I'm certain he wasn't the only one) understood completely. To produce a real production car that weighs 2200 pounds, to pass real safety standards, that real people will buy at your stated price of $40,000, with the items real people would expect, and without the car's developer being fired for financial incompetence, you would in fact end up with a Miata sized vehicle.

Geez!

 

Ultima GTR can be had for $30,000 shipped from the U.K. you put it together, along with the engine. US road legal too. I brought it up to disprove your theory that light chassis = weak cars. The frame on that car is quite lightweight, yet it can handle a 1000+hp SBC... odd isnt it?

Who said anything about making carbon/aramid monocoque cars? What did I tell you about these so called "paper" thin bodies, hell even the prototypes bodies are quite thick and very durable.

I was talking about my particular design that's $80,000, I'm sure if I changed the powerplant, deleted some exhaust components, took out the Powerhaus II/Porsche gearbox, used GM wheels instaed of Kinesis/Fiske/Forgeline, and deleted the Brembo/Porsche calipers and used Vette wheels, minus some profit, I could get the car down to around $45,000 out the door without too much of a problem. It will still retain the same chassis design, same composite body structure, or possibly substitute it for a FRP style body and cut a few more thousand dollars off of it.

And here you go again, knocking off small volume production cars and one of the best sports car fabricators in the world.

Again here you go with your Miata sized BS... yes, if you want to a run of the mill stamped steel chassis fine go ahead, but there are better methods now that are used in mass production, look at hydroforming, the Vette's frame rails were done this way... weld several hydroformed members together and you have a quasi-space frame design that is very lightweight, and if engineered properly will be very rigid. Crash structures can be made of plastics, composites, etc. etc. The body can be done with fiber reinforced plastics, this is in wide spread use now, and the molds can allow for the body to be "hung" on the frame of the car, so now you have a short but rigid chassis, say with 102"-104" wheelbase, 65" track width or so, 18" wheels, etc. etc. make the chassis length approx. 130", add the crash structures, around 150"-160" in length, 65"-70" width, wrap the body around it and you have a very lightweight automobile utilizing today's standards in mass production techniques while retaining a lightweight and rigid chassis while still maintaining a "full car" presence.

So now I just told you how to do it with today's production standards, so whats your excuse now?

 

Um..... aren't Corvette's hydroformed rails made of "steel"? If I'm not mistaken, it's a hollow tube that's formed by placing a tube in a mold, and pushing high pressure fluid to make the form. I'm not exactly sure how this plays in your "stamped steel is heavy" view, but we are still talking steel here.

Stamped steel is less labor involved than taking lots of steel bars and crossmembers, and welding it together. Viper, Ford's GT, and to a degree, the Corvette are all variations of an inner chassis. Porsche's is stamped steel as is Camaro. All handle just fine. Viper is fairly heavy, Camaro is relatively light. Team Corvette had to put in extaordinary time to pare weight from the Corvette, and Ford GT's weight is being kept in check with extensive alumunum. Guess stamped steel isn't always heavy, huh?

As far as who started talking about carbon/aramid monocoque cars, you infact did when you brought in the F1 to the conversation.

I really have to give it to you on your convictions. Not sure you understand what I've been saying, but you sure are immoble in the face of anything that disputes your view.

Ultima costs $89,000 without engine or drivetrain (http://www.ultimasports.co.uk/usa/gtrchassis.html), so good luck in parring off $49,000 off of the car's price (we are still talking about your initial $40,000 car, right?). Just the basic pieces cost $28,000. That's fine for just having pieces scattered on the floor, but then you need labor to put it together. You also have to add in those "accessories"... like brakes, an electrical system, paint, an engine... (http://www.ultimasports.co.uk/usa/prices.html)

But, don't forget to add in the things the Ultima doesn't have that you'll need (there's a reason it's sold as a kit car). Things like 2.5mph bumpers, side door beams that pass federal automotive standards, OBDII emissions hardware, Catlytic converters, smog pump, and other pollution hardware, driver and passenger airbags and related hardware, and a whole host of mandated items. None are very cheap, and most certainly are not lightweight.

Regarding plastic chassis, if you have some secret molecular formula, then you are sitting on a goldmine, and perhaps should get together with PacerX or one of the other automotive suppliers here because you guys would certainly be rich. The problem with plastic chassis is that over time it cracks (weakening it), doesn't hold up well in tempreature extremes, or it tends to sag with age. Pretty much any automaker would kill for a plastic chassis that holds up as well as steel or alumunum, but despite best efforts, that hasn't happened yet..... unless you yorself have broken that barrier (remember, race cars don't have to last 10 years or more).

But getting back to the subject, if you find a way to make a car the size you propose, at 2200 pounds, and sell it for $40,000, without running the company into the ground you'd be a revolutionary. But as far as the present goes, your choice still lies between a Miata sized car or an $80,000 one.

Now excuse me, I have to go to bed.... and finish carving on my chest.

 

I was involved for a time with the Shelby Series 1, which I would like to state for the record is a disaster of an automobile. The price (if I remember correctly) started at $139,000 and moved WAY north from there.

Body panels were produced outside in Mexico. I don't mean "outside supplier" here, I mean OUT OF DOORS... as in "HEY! this place doesn't have a roof!!!!" Fits were horrible.

The Series 1 had full GM Powertrain support for the engine (which began as a modified Aurora V8).

Corvette components were all over the place (switchgear, HVAC controls, etc...).

In short, GM had contributed considerable help to the process, and the car STILL couldn't be made for $139,000. The car was a financial loser from the word "go", and the accounting had to have been suspect to make the business case and budget tracking work out. I'm not talking about fraud here, just stuff like having an engineer work on the program but bill his hours against a different one for budgetary purposes only.


Now... let's talk about materials for a second...

Steel has wonderful properties. That's why it is used all over the place. But when people say "steel", the term is used too generally. There are literally thousands and thousands of steel alloys, from 26,000 psi mild steel (DQAK) to 220,000 psi Inland M220 to armor steels like the Maraging steels.

M220 has ~10 TIMES the yield strength of mild steel. Throwing them both under the name "steel" is kinda vague, they are both steels, but have radically different characteristics. Let's talk SPECIFIC steels if we want to make comparisons to other materials.


Plastics have their own set of problems. First and foremost is called "creep". Even with small loads applied, plastics will continue to deform under load indefinitely.

Strengthening the plastic with glass or aramid (graphite) fibers helps, but adds cost.

Plastics are sensitive to UV light, which can weaken them considerably.

To make plastic composite panels, you either need big. expensive tools or you have to hand lay stuff. If you are going to hand-lay, you will invariably suffer from poor dimensional repeatability without either throwing tons of parts out or tons of hand-work to get them back into shape.

So, since we are talking about a low-volume car here, that means there is little chance you can afford volume production composite panel tooling and still make money. That means we are talking about hand-laid parts and the inevitable poor fit quality that comes with them.

Larnach, have you priced these PRODUCTION tools? Not this hand-laid mat garbage, the real deal.


Now... here's the CRITICAL difference between steels and composites....

ENERGY MANAGEMENT.

Composite panels and structures SHATTER. Steel panels and structures DEFORM and chew up lots of energy to do it. Corvette DOES NOT rely on body panels to manage collision impact energy, it relies on the steel frame and supporting structure to do it.

I have yet to see a production composite structure (NOT PANELS, actual structure) that can handle a 30 mph frontal impact with adequate safety. Even race cars have incredibly strong steel/aluminum/titanium structures in them to accomplish the same thing.




Here's the hard, cold fact...

Shelby, with HUGE support from GM, could not pull off a lightweight, high performance car for less than $139,000. They then skimped left and right and basically went under trying to do it at $200,000.

You are now proposing a car with HIGHER performance than the original Series 1, for considerably less money.

Here's an honest question for you Larnach:

Are you familiar with applicable Federal Motor Vehicle Safety Standards for automobiles in the US? Do you know how many parts and cars you are going to have to destroy to meet them?

 

I give up on your negative attitude towards everything related in this thread to realisticlly bring a car to the market... Yes, if I had the money I could bring a $45,000 car to the market that would beat the pants off most cars, why? Because I and a few other builders and work at low profit margins, large companies can't, that's what seperates the corporates from the hobbyist/enthusiast.

PacerX, I'm well aware of the standards set by the government, I haven't gotten to in depth with the crash testing and allowable loads on the passengers, but I have been reading up on the CAFE standards, which don't seem to be a problem provided I use a mass produced engine built for the same vehicle class along with it corresponding emmisions equipment. I'm also aware of the fact of how many cars are needed for the safety test, however for low volume cars, there are provisions in the standards, like I said, its a money issue, this isn't going to be some massly produced vehicle, maybe only 200-300 a year at the most.

I'd like to see a build sheet and labor cost for that Series 1 car because that seems pretty outrageous in parts alone. I've built whole vehicles, starting off with sport quads, powdercoating, painting, plastics, motor rebuilds, gearbox's, etc. etc. since I was 14, currently I'm finishing my bronco project and painting the underbody as soon as I remove 2 more fuel lines and the exhaust, I'm aware of how fast the little things add up... fasteners alone on my Bronco have cost over $300! And I'm not even a 1/4 the way through the thing.

 

If it wasn't hard, there'd be a cottage industry in the US. But we've only got Saleen, Panoz, and Shelby (have they even made any cars?) - with Panoz the only one to deliver a car for less than $100K.

BTW, CAFE is easy - you don't have to meet CAFE. You can just pay the government a "fine" and keep selling cars. Certain German manufacturers have been doing this for years....

...it's those other requirements that are the killer.

 

ACO and the FIA specify composite crash panels for a reason, they absorb energy, and depending on the weave pattern, and the direction its laid into the final product, it can transfer loads as well.

Here's a few examples of composite crash panel technology that I have take at various events.

http://www.siknor.com/EGDome2002.jpg

http://www.siknor.com/EGCaddyNose2002.jpg

So now you've seen composite panels designed to absorb huge impacts at high speed. I don't know the technical specifications, or the exact speed that these are tested at, but the ACO rules are available in .pdf format throughout the web.

Again, I'm not going to argue cost with you because I have the quotes in hand as well as the build sheet, I don't think the numbers lie.

 

Yes, but what is the tax now in 2003, it was raised from last year. I don't know the brackets, but the lowest bracket is a $12,000 tax I beleive, the highest being $3500, this just adds cost to the vehicle.

I'm not even seriously thinking about the standards at the moment, I don't even have the money to build the car... I'll leave that for later. All things aside, I think we can put this "vaporware" car on the back burner.

 

As well built as that may be, and while it can abosrb energy, CF still doesn't deform as was said before. what will happen is the CF will take a large shock load and shatter (also possibly spraying sharp objects around if the kevlar weave is cut), then whats to absorb the rest of the inertia? Steel will bend initially from imnpact and then continue absorbing forces, vital to multiple car wrecks or even single car wrecks.

I dont think anyones saying a 2200 lb car with a 430 HP engine is automatically weak, but to do so in large production volumes (200K year) and trying to make as much money from every car as possible it simply wont happen. hydroformed pieces on the corvette, a car that can afford to have some complexity, only come in a few places, making space frames is very space consuming as well, leading us back to the large exterior, small interior design. Looked at a space framed car? any high end exotic, they're massie exterior wise but only have 2 seats, why? the chassis takes up a ton of room. A monocoque chassis would work perfectly for an Fbody in reducing weight and keeping rigidity, unfortunatly convertible monocoque cars are rather weak since it relies on the entire structure to provide support.

Aluminum has been used as well, the Ferrari 360 modena, with all its extra cost and COMPLETELY aluminum chassis, it only has roughly 200 lbs on the corvette which uses steel framing. Al alloys used in car production (things like T556 Is the alloy number I believe) are much lighter, and also about 1/3 as stiff as steel. That means you need to use nearly 2/3 as much dimensionally compared to steel, very space engaging and the weight saving comparativly aren't anything to brag about. Then you also lose the minimum stress failure point of steel, bang on anything al with a 2 lb hammer for long enough and it'll break, not so with steel. Wouldn't be very good if all of the sudden 10 year old corvettes starting breaking main chassis components after years of everyday abuse.

On the whole Fbody thing, the lighter the better, pony cars were made in order to satisfy people who wanted to do more then just tear down dragstrips and thats how they should stay. Sticking an IRS out back is iffy, if it isnt a double wishbone design then forget it, trailing arm (ala ford) offers no real handling benefits over solid axle and costs/weighs more as well. Keep the engine far back in the chassis, not just the body, improves weight distribution and helps the car feel nimble, something it should. You can keep the wheelbase, just improve interior size as well and you're set, its sales will be 90% dependant on the feel of the car as it drives and the exterior looks of it.

 

Yes, a spaceframe chassis @ 200,000 units a year is impossible, no arguments from me on that.

Back to the subject at hand, like I said before, aluminium hydroformed subframes, welded together, hell maybe even steel that would reduce cost further and increase the roll over strength at the expense of about 300lbs or so. Hang a body on the car etc. etc.

 

or maybe we could finally get a full perimeter frame and reduce body panel weight that way, fat chance I know

 

Don't get mad. Afterall, we all have no idea what we are talking about!