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Making a concept car street legal

03-08-2006, 04:25 PM
Lately I have been interested in making my own concept car. Nothing big or fancy, but If you remember the T-rex 3 wheel cars that run with a motorcycle motor, that is similar to what I want to build. Only I want to have 4 wheels and ran with a Harley v-twin motor, and Fiberglass body. Not really detailed and flashy something simple and nice. But I was wondering what it would take to make it actually street legal. I've tried searching on google but haven't had much of any luck. If you guys have any info on this I would definatley appreciate it. Thanks.

03-09-2006, 12:12 PM
if you plan on making it a performance car then you might wanna reconsider making it 3 wheeled so it would be classified as a motorcycle and if you want something like the t-rex on 4 wheels then you'd have to add a whole lot of heavy safety stuff to make it stret legal and i think motorcycles get lower emmisons requirements so if its 3 wheeled then you wont have to detune it too much

03-13-2006, 02:34 PM
Hey, we've got the same name. Imagine that. Anyways, that sounds like an interesting project. Since you are looking to build it yourself, you might be able get it classified as a "kit car" for licensing and insurance purposes.

But you need to remember what you will use as a base for it. Will you fabricate your own out of steel or aluminum or use one you can just buy? And you need to make sure you know what your doing when installing the engine so that it doesnt get screwed up. Also think about the brake system

To make it street legal, as far as I know, it needs to have the following (these are basic requirements for motor vehicles to be street legal in MN):

-Must meet or exceed EPA emissions requirments
-A bumper height of no less than 6 inches (not sure about that one, but there is a minimum legal height)
-Headlights/taillights (taillights must get brighter when braking, like regular cars)
-Turn signals
-3 mirrors
-Muffler (I think)
-Catalytic converter

Thats all I know of, although there are undoubtably more minimum requirements. And you must (obviously) get some sort of application approved or "Yes that's ok" from your state government. So know what has to be on it. Good luck if it all works. Post some pics of it when you finish.

03-26-2006, 12:11 PM
it will vary greatly from state to state, but most states are pretty simular in that, if you start from scratch, they will make it very hard to get past the emissions part of the inspection.

You are really best off starting with an existing car/motorcycle, and incorperate the frame into the design so that you can keep the title listed as what it started out as....

This can be very quantitive though, depending on how far you are going. I have a concept car I've been toying with the ide of making forever, and would be pretty much a ground-up build....I was going to buy some cheasy older car and incorperate the frame numbers and fire wall into it, but it would mostly be for legal purposes only.....the car would not resemble its stock form.

12-09-2009, 09:37 PM
Hello everyone!

I have several ideas I have been floating around in my brain. Yes I actually have a brain!:lol2: The main one I have been working over in my brain, all I have so far is engine ideas, transmission ideas, drivetrain, suspension, and brakes. I have several ideas for body styles, but that would depend on what the vehicle would be used for.

example: I have a full racing version similar to the Lemans Series cars; the Full cockpit Prototypes, and GTP's like the Corvette, Ferrari, Viper, and Lamborgini. I have a Racing version similar to the Mustang, Camaro, Challenger, Charger, and Porche 911. I have a Rally Cross version similar to the Subaru Impreza WRX.

My road version is whole nother ball of wax, I have no clue what shape to make it. All I know is I would have a 2 door and a 4 door version, 4cyl and 6cyl engine options, Automatic, automatic w/paddle shift or sportstick, manual transmission, Independant suspension front and rear, Vented Disc brakes all 4 wheels with ABS and Traction Control, all wheel drive/front wheel drive/rear wheel drive option.

01-13-2010, 11:34 AM
hi all, i am kiernan cough. the idea of using a pre-existing firewall is probably the easiest way of getting over the biggest hurdle- being able to register the car. some states, such as maine where i live make you inspect a car annually. in maine they check the brake lines, the e-brake cables, all running lights and signals, exhaust (usually just a sniff test, some of them run a scan tool if it's an OBD-II car to check your cat) corrosion damages, tire wear, suspension linkages, and steering linkages. things to keep in mind. i've got some designs myself that i plan on putting together over the next 10 years. certain things i will do are use a space frame chassis, to save on weight. aluminum undercarriage, to prevent corrosion. carbuerated engine, with electronic ignition for in inconspicuous yet harder to fail exhaust. a central recessed channel, covered by a bolt on plexi-glass panel and sealed at the ends with rubber fittings to protect brake lines from corrosion, while keeping them visible to the mechanic. tires with a reasonable tread wear rating. 4 point safety harnesses which are legal, and safer than traditional 3 points (5 points are illegal in maine) steel reinforced fiberglass which is cheaper than carbon fiber, but still easier than metal forming and lighter than a metal body. i hope my thoughts may become useful to you when you are making your dream machine a reality. although, for your particular design they may not be of much help.

01-13-2010, 12:06 PM
Hello everyone!

I have actually given some thought to the exhaust. I was thinking on dual exhaust, depending on the engine; 4cyl, 6cyl, or an 8cyl. For the 6cyl and 8cyl engines I like a straight dual exhaust system. On some 6cyl engines you might be able to get away with a 2 into 1 into 2 type of dual exhaust system with a single catalytic converter.

For the engines, I am not sure if I want to have a normally asperated/carbureted or Fuel injected. There are pros and cons to both. I was also thinking of having a turbo-charged 4cyl version in one of the car ideas. The one idea I had for a car had 2 afterburning jet engines, But I don't think that would be good for the road, except for land speed record setting! :screwy: Yes, that is a screwy Idea, but sounds like fun!

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