Thanks UtahSleeper. Good idea on contacting someone that has done it before. I'll give them a call.
Here are the specifics that I have learned so far about importing a non-US model to the US and California. I have done this research over the course of the past several years, so everything may not be completely accurate, as I'm not a lawyer or particularly an expert on this, but it should point you in the right direction, should you decide to take on the task of importing a car.
Essentially there are 3 entities that you must satisfy in order to import a non-US model car. There is the federal DOT, the federal EPA and California Air Resources Board (CARB.) DOT requires that all cars 25 years old or newer conform to the federal safety standards for the year model of the car. If the vehicle is over 25 years old, it is completely exempt from this rule. If you import a car that is less than 25 years old, you must use a certified Registered Importer (RI) to get the car in the country. When the car is in their hands, it is essentially in a customs quarantine. They will perform the work on the car necessary to bring it up to the federal crash standards for the year of the car. The EPA standard works similarly, but only applies to cars 20 years old and younger. A RI must make modifications to meet the EPA standards. Basically, this makes it prohibitively expensive to import the car, so no one bothers. If you are lucky, the model car you are interested in may be functionally identical to the US model, other than being rhd, having a kph speedometer, etc. In that case, you can request a letter from the manufacturer stating that it meets all DOT and EPA regs for the year and you're good. I'm unclear on whether you need to retrofit a mph speedometer or not. This is a requirement when an RI performs modifications, so you still may need this. It is illegal to import parts and assemble a car for the purposes of getting around these regulations.
Most of us are interested in cars older than 25 years, though, so much of that does not apply to us. California has stricter smog laws than other states, so you should research your state's requirements if you're not in CA. California used to have a sliding 25 year smog test exemption like the federal one, but that was eliminated by The Governator when he was in office. This has never exempted you from having smog equipment on your car, it just saved you the $40 every 2 years and a trip to the smog test shop. California requires you to have your car inspected and certified by a BAR referee if you change the engine in it. It is legal to install any US model engine in a road car if you can manage to get it BAR reffed. They require that you have all of the smog equipment from the car that the engine came out of. So, if you decide you want an F20C engine in your dime, you will need all of the smog gear from the S2000. Cars that are year model 1974 and younger must be smog inspected. Cars that are 1973 and older do not need to be smog inspected. If you install an engine that is newer than 1974 in your car that is older than 1973, you need to have the car BAR reffed and you are subject to smog inspection. Engines that were never federally certified are illegal to install in any road car. Examples of these are the RB series GT-R engines, SR20DET, 20v 4AGE, etc.
I pretty much outlined the process for post-1974 cars in California in the first post, but there are some additional regs. I didn't inquire about them, but the documentation from CARB seems to indicate there is a different procedure for 1968-1973 year model cars. They specifically state that a car older than 1968 does not need to be certified in order to be registered.
If you call CARB, they will tell you that there are two labs that can perform the testing. This is untrue. They may give you the phone number for a lab in Napa, but this lab is not currently (as of 11-1-2011 at least) contracted by the state, so they can't help. I talked with the owner of the lab and he says it is a huge pain to deal with the state, so he doesn't have much interest in doing it any more. It is also hard for him to justify the cost of employees for such a niche market. That leaves us with only one lab in SoCal called California Environmental Engineering (714-545-9822.) George is the guy that deals with grey market cars, so it's best to have a chat with him. He seems like a very nice guy and was very forthcoming with all the information that I asked him. When I buy a car, I plan to get a detailed description of the test procedures so that I can perform the tests myself prior to bringing the car to him. My goal is to pass the first time. I was told that he is kind of a shady character, but I did not get this impression from talking with him. CARB has local offices around CA, so you can call them and ask to speak to the person that deals with grey market vehicles and get information specific to your car. I have not called BAR to figure out what the reffing procedure is, but I would expect to breeze through with a fresh certificate showing that the car meets the required standards.
Again, I'm just a regular car enthusiast that managed to navigate the red tape in order to get a bit of an understanding what is involved in importing a grey market car. You should do your own research and not just take my word for it.
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