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I wanna build a car.

  1. Oct 21, 2009 #1
    So I've decided that I want to build a Dodge Charger, in the style of the 60s or 70s, after I finish engineering of course.

    http://en.wikipedia.org/wiki/Dodge_Charger_(B-body)

    Either the one at the top of the page, or the one under the 'second generation heading. It's more of an aesthetic choice in that regard. I don't know a whole ton about auto-mechanics, but I think I could pick it up quite easily.

    Now while I feel confident I could deal with all the mechanical works, and learn anything else along the way, I don't want to risk building the frame myself. From what I've learned the tolerances are really low, especially for muscle cars. Any errors could make the car destroy itself if what I've learned is to be believed.

    Would it be easier to simply get that kind of car, and re-build it? The only thing I'm worried about there is the age of the frame, and whether or not it would still be safe.
     
  2. jcsd
  3. Oct 21, 2009 #2

    DaveC426913

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    You're going to jump straight from the cradle to the marathon without knowing how to walk??
     
  4. Oct 21, 2009 #3
    Well it worked for electronics. Why would it not work here?

    I set impossibly high projects for myself, then learn lots along the way trying to meet them.
     
  5. Oct 21, 2009 #4


    Definitely.


    Building a Charger from scratch can be overwhelming at times.
     
  6. Oct 21, 2009 #5
    Alright, well then the two main concerns are cost and safety. Is a 50 year old steel frame still reliable in a high-stress situation? I know chargers had full roll cages. Also I doubt that I'd be able to acquire a vehicle like that, even in bad condition for a good price.
     
  7. Oct 21, 2009 #6
    I wouldn't bet your life on it. Its common practice to box the frame of old car chassis in order to increase strength and reliability. As long as you know how to spot weekend areas and the frame and are good with a MIG, it should be fine.

    Your biggest obstacle is cash. Electronics is a much cheaper hobby than restoring old cars. Be prepared to spend 10 times on what the car is actually worth to rebuild it.
     
  8. Oct 22, 2009 #7
    So what is boxing a frame?
     
  9. Oct 22, 2009 #8
    Be honest how much do you like working on cars and what is your cash flow like? If you are looking at something like a kit car be ready to be paying around 100k when the project is done. I'm guessing scratch built or frame up restoration will cost about the same. Also do you have a two car garage that you could tie up for two years? Do you have any experience welding, machining, or metal working? Do you have or have access to a welder, machine shop, or sheet metal shop? And finally all old Chrysler's from 60s to 80s are of a unibody construction. So there is no standard frame, just a sub-frame for engine and drive train. The rest of the structural rigidity comes from formed and welded panels.

    I'm not trying to dissuade you from doing this project just want to let you know what is needed before you jump into a very deep pool.

    I have an old 65 Cuda that I've put in three years into. I was lucky that the only damage to the unibody was a front passenger side pan that needed to be replaced because of rust. It was easy in that I was able to pick up an aftermarket one and cut the old one out and weld the new one in. As for the engine I've done some light machine work to the heads (porting), upgrades the bolts, crank, rods, pistons, rockers, and valves Changed the cam, and replaced the ignition system with a computer controlled one. And after all of that work I still have the carbs, clutch, trany, and rear end to mess with. Also I'm thinking of trying to shoehorn a turbo setup in.
     
  10. Oct 22, 2009 #9
    Yeah, I guess I am trying to dive into too deep of a pool all at once. I like mechanics, it's an interesting subject to me.

    I don't have a ton of metal working experience to be honest. I guess those skills aren't things that can be learned on the fly?
     
  11. Oct 22, 2009 #10
    Dont get discouraged so easy, I dont think anyone is saying you cant or shouldnt reach for your dreams but they are trying to get you to be a little more realistic. Building a car from scratch would be a huge undertaking, and imo if your going to start from scratch why limit yourself to a car that has already been made? If you want a charger it would be more logical to buy one and rebuild it, anything can be fixed it just might be very expensive and very time consuming, if you are inexperienced at what to look for make sure and get a second opinion from someone in the know. If mechanics truly interests you, it will be a very rewarding hobby and a great way to spend time and money. When you finally get your car done you will be a true hand at lots of different trades and will know a lot more about things you didnt know about before, unfortunately one thing you are guaranteed to learn is that it is a lot more work and is a lot harder than you imagined it could be.


    What is a better way to get experience than diving in and doing it, just remember some will not be fun nor easy experiences and some will even be terrible and expensive. IMO everything is learnt on the fly, how can you experience new things sitting still? There is a website and if I remeber right their name is smart flix or something like that, they have video courses on everything from airframe construction to welding to gunsmithing, basically every blue collar trade or hobby you can imagine. I have used their vids in the past and some leave a little to be desired as far as video quality but they have great content and you can keep them as long as you want so you can master the lessons.

    P.S. Boxing a frame is when you weld a plate onto a c=channel(which most car frames are) inorder to make it essentially a box or at least a rectangular tube.
     
  12. Oct 22, 2009 #11
    I see, well I guess it's something I could peruse when I have more spare time. The reason I wanted to build it was so I could make modifications to the existing design that would improve performance, and efficiency. Speaking of which, you wouldn't happen to know where I could get the specs for the car from? Google has failed me thus far.
     
  13. Oct 22, 2009 #12
    If older Muscle cars interest you , find something in good shape (body wise), and start working on the engine. If you want to work on cars in general look for an older VW. They are fairly simple cars to work on. Or look into something from the early to mid 90's. You should be able to find something inexpensive and there are a ton of OEM parts.

    If you want to tune/hot rod something, again look for something that interests you and has a large selection of aftermarket bolt on parts. GM and Fords from the 60's and 70' will fit nicely. Or look into again something from the mid to late 90's.

    Welding is very easy to pick up as long as you go with a GMAW or MIG (wire) system. You could be taught by someone who knows what they are doing in a day, and in a week be putting down fairly good welds. Doing SMAW (stick) or TIG are much more difficult processes. As for metal working, layout, cutting, and welding are fairly easy to do, if you get a bit of instruction from someone who knows what they are doing. Machining is hard but not difficult to do, just damn expensive to start. As for sheet metal forming, that is difficult and a damn art. But sometimes I just don't have the patients to use an English wheel.

    Just figure out what you want to do and start with an easy or simple project. As you build up your confidence and skill sets you can tackle harder projects. My first car was a heavily used 83 Chevy Surban. I started out with doing simple stuff like spark plugs, changing oil, and the air filter. Moving up I rebuilt the carb, tuned it, re-jetted the carb to stop it from dieseling, replaced the spark system. Eventual, after working on it for several years, I had rebuilt the engine, from the block up.
     
  14. Oct 23, 2009 #13
    Yeah, I find older muscle cars really attractive.

    The reason I'm picking such a huge project since I'm new, is because I find I learn when I have massive problems to solve.

    I had guessed welding wasn't the hardest thing in the world, but I heard it takes skill to work with some metals. My dads been wanting to get a MIG and a TIG welder for some time now, I don't think it would be too hard to get those.

    I have some experience with a milling machine, although as you mentioned they're really freaking expensive. As for sheet metal...that seems like it would be 'fun'.
     
  15. Oct 23, 2009 #14
    I would have to say I am the same, the problem is there are loads of other people that think the same thing and the more people that want something the higher the price. Old muscle cars are getting to be very expensive and over valued IMO, people seem to ask for prices based on what you can get if you do loads of work to them and not what they are really worth. Some cars arent far from scrap yet the seller will want classic car prices so be prepared. If you could keep an eye out for a bargain car while working on smaller projects to help you get up to speed will be a far better option than paying too much for a car just so you can get started on your main project, be patient and a deal will come your way.

    That is true but you can also learn with small problems to solve and you will be less likely to travel too far down the wrong road. When coming up with a solution it is very easy to succeed only to find out later that that your supposed solution has created more problems for you. Until you can learn how all the systems work together you will be walking on thin ice when solving problems and that can get very expensive and time consuming very quickly when you are having to re-do things.

    Getting two pieces of metal to stick together with a weld is easy, getting a weld you would trust your life to is a different story and if you dont take metalurgy into consideration you can actually make your car weaker by doing a weld wrong, Lincoln make a book that tells you everything you need to know about welding any kind of metal, I think it is called the arc welders handbook if I remember right. If it was me I would only use a MIG on non-structual welds, using a TIG is the highest quality weld by far but also the most time consuming.

    There not that bad, I bought a bridgeport a few years ago for 3500 dollars, it was in good shape and came with a digital readout. It doesnt take long to save yourself 3500$ when you are making your own parts and tools. I found though that the accesories is where the costs start to rise. You will find it easy to spend more on the tools you need to use the mill than you spent on the mill originally. It is interesting to me though that you are worried about the price of a tool while at the same time you are saying you want to start probably the most expensive hobby out there.
    Sheetmetal work is fun and it is also a great way to reduce stress, grab a hammer and start banging on a piece of metal. When your done you will be stress free(unless your not getting the result you expect), and you will have a piece that was flat and boring a while ago, that is now a fender or a fuel tank or whatever, very rewarding.
     
  16. Oct 23, 2009 #15
    I did manage to find several books on welding, I'll dig through those later.

    I guess you're right about the project size. In electronics I was virtually worry free cash wise. I blew so much stuff up. :D I can do basic things like changing the brake fluid, oil changes, filter changes, etc. Those things I just picked up by doing them with my dad.

    Might as well learn more before I start trusting my life to my work.
     
  17. Oct 23, 2009 #16

    DaveC426913

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    Another risk is that you might blow yourself up.

    Messing about in electronics might net you a nasty shock at worst, but you start welding and cutting using industrial tools when you are inexperienced and you might very well lose a body part.

    I'm sure you are a good learner and won't take unnecessary risks, but there's no substitute for experience. There's nothing you can do to mitigate the cumulative risk of injury on this giant project that comes from a lack of experience under your belt.

    Not trying to discourage you, just urging caution.
     
  18. Oct 23, 2009 #17
    I would recommend like before Arc Welding Handbook by Lincoln Electric as well as Pipe Welding Procedure by Hoobspar Rampaul(if you plan on using a tube chassis), there is also an author named Carol Smith who wrote alot of different books on subjects like Chassis engineering, performance suspension engineering, engine tuning and such. In my home town the local technical school offers night classes on welding, automotive mechanics and machine shop which if offered in your area are pretty easy to fit into a schedule and might be decently priced. You could also find a small fabrication shop and apply for a entry level position which will probably involve a broom but if you let them know it is your intention to learn everything there is to know about fabrication they would work with you since it is my experience small buisinesses love to teach skills to their employees(as long as they are making the effort) since it makes you more valuable to them and that usually means a bigger paycheck for you.

    The project size isnt so bad but the trail to reaching it is going to involve a bunch of smaller projects if you go step by step you will have far greater chances of reaching your end goal. The first is to decide what you really want, you stated above that you like the chargers and would like to build one, you also stated that you would like to modify the charger to make it more efficient. Do you want to build a car that looks like a charger or an actual charger, because if you choose looks like a charger it will increase your chances of reaching the goal of making it more efficient. The charger is a very heavy, un aerodynamic car that is powered by old technology. The easiest way to increase its efficiency is to make it smaller and lighter as well as drop in an engine that uses newer technology, so if you want an actual charger it will limit your options but if you want a vehicle that looks like a charger you would have almost unlimited choices to reach the end goal. Fiberglass, carbon fiber, aluminum construction would decrease the weight. Subtle changes to the shape would increase the aerodynamics and decrease drag. If you want it to handle like a charger(which isnt very good by todays standards) or if you want it to handle like a new sports car the old design would limit your choices if you built a new design you could incorporate new technology such as independent suspension easier. Old chargers used very inefficient big block engines(for the most part) if you could drop in a new small block hemi which puts out practically the same power as the old engines but with far higher mileage it would help you. So basically you can either modify an existing car or you could design the car you want. To modify an existing car you could get by with learning welding, mechanics, and body work but to design a new car on top of those you would need to learn some structual engineering, suspension geometry and design, aerodynamics, mold making(if you use carbon fiber or fiberglass), metalworking(if you use steel or aluminum), metalurgy, and on and on. Just look at a college that offers automotive engineering and check out the curriculum they need for a degree, you wont need everything they recommend but you will need to learn a lot of it.


    How about buying a welder, cutting torch set, a grinder and a few basic tools. Then start by building a go-cart which would include lots of welding and fitting but no suspension you would learn a lot and when finished you could sell it and build a sandrail which is a little more involved and includes a suspension when done with it you could sell it and start your main project imo that path would be fun as well as educational.

    You already have a vague goal so all you need, is to get a more precise one and then make a map of the neccesary path to reach it.
     
  19. Oct 23, 2009 #18
    I'll have to try and pick those up at some point. Getting a job at the moment isn't really practical, but there's always work to be done around here, so I could learn on other projects.

    That's one of the goals I settled on once I had decided that I wanted a charger. The main goal is to produce a charger that is just as loud and powerful as the original, but that runs better. The right sound is important.

    It's hard for me to make more definite plans without actual specs for the car, and they're proving hard to find.

    I guess I need to test drive a charger to know what they're like. Judging from the weight and what you've said about the suspension I'd guess they handle somewhere in the range of mini-van to that of a silly cow?

    I figured a smaller engine would be needed to achieve any noticeable fuel efficiency. Perhaps if I could get my hands on specs for the old engine, I could make improvements to that design, then scale it down. The question I have is, can a smaller engine still output the same power? There's no point to a weak muscle car...


    Sounds like a plan. The go cart actually sounds kind of fun. I don't have the same open space to drive it as some do, living in a suburb and all. There's an old rotor tiller I could take the engine from to power it. I could probably get away with using the wheels from it. Maybe even mount the tiller on the go cart and use it to take out tailgaters!
     
  20. Oct 25, 2009 #19
    Sound a priority? Well if you want the old charger sound your stuck with needing a big block since you can get a small block to sound good, but imo you cant get a small block to sound like a big block. If you want the best sounding combo imo you are going to need a 426 hemi which wont get much as far as mileage goes but the power and sound would be there. One down side though is a hemi will cost between 10-15,000 dollars from mopar and if you find a charger with a hemi it will add about that much to the cost.

    What do you mean by specs? Do you want the original power numbers or do you want the size of the wheel bearings? I'm sure you can find shop manuals from mopar, possibly even online for free.


    It sounds to me like your more interested in the sound and looks more than the performance and handling. The stock suspension can be upgraded to handle better by adding bigger brakes, stabilizer bars, shocks, etc;.


    Are you really wanting to build a foundry and cast your own "improved" blocks or am I mis-reading this part? If I understood correctly you will probably be better off starting a corporation and going public, then leading that corporation to the ends you seek. If you truly want to "build" a car and all its components you will need some large finacial backing. ICE have been being upgraded for a 100 years by some of the brightest minds in the world, I really doubt that much more efficiency can be squeezed out of them by subtle changes in design, however imo if you could change the materials of the engine so that friction was almost non-existent you could get more power out since less would be loss.
    Yes, you can get similar power from smaller motors, its just harder and more expensive. I once had a shop teacher that said that you can get just about any power level out of any engine and the only things limiting you is your pocketbook and how long you want the engine to last. Look at top fuel dragsters, they put out thousands of horsepower but are very lucky to go more than a 1/4 mile without having to be rebuilt, and quite a few blow-up before they even go the 1/4 mile, whereas lots of stock motors only puts out @ 300 hp but will last for hundreds of thousands of miles.


    If you want a fast one find a couple old chainsaw motors(2-stroke). If you want cheap and easy the tiller(4-stroke) will work fine.



    By the way I was watching powerblock sunday last week on spike tv and they were building up an old cuda, it would be very similar to a charger and would help you to see what you have ahead of you. The show was Muscle Car and I think you can find the videos on spiketv.com. Saturday and sunday from like 9 in the morning till 11 I think spike has what they call powerblocktv which has 4 good shows(horsepower tv, extreme 4X4, trucks, and muscle car)if you have cable check it out.
     
  21. Oct 25, 2009 #20
    I've been trying to find actual dimensions for the car, any information I can get.

    Performance and handling are the major areas, but I think there's little point to building a car like this unless looks and sound are a priority too.

    I'm not claiming I have the genius to make a huge revolution in ICEs, I meant take the old design of the engine and apply new technology to it.
     
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