Two ppl told me (for US) that it's only legal to install an engine of the same or newer year. This means it's illegal to put a 06 civic si engine inside an 07 fit. Is this true? If so, what's the rationale? I mean, my fit will be a econ car primarily, but it puts an ease of mind to know if the option of swapping an engine is there in case i get bored w/ driving slow.

 

As far as I know any engine swap can be deemed illegal because to my knowledge, every motor is unique to the VIN of the car that it came in and can be traced back to that VIN if the authorities feel they have a need to do that. Technically speaking though, in California if the motor you swapped into the car is smog legal and if its modified with CARB approved parts with no big visible signs of modification, even if a cop was to ask to see under your hood he would never know whether or not that motor came in that specific car or not.

So theoretically it is illegal but the chances of getting caught is so small that if done right, you'll never get caught. Keeping a low profile is the best way to getting away with anything related to engine modifications. If a cop cant tell apart between you and the average joe then you got nothing to worry about.

 

I think that any swap that is approved by the CARB (with a sticker from the smog referee in your engine bay) is legal. There are however lots of tricks that need to be done to get that CARB sticker, ie, all smog equipment must be installed, and the motor has to be "newer" than the car. I don't know all of the ramifications, as I have never owned a car with a swap, but a quick Google search came up with:

http://www.norcalcrx.org/library/calegalswaps.shtml

Hope that helps some.

 

It will void the factory waranty, but legally to do the swap is all up to if you have to pass emmissions or not in your local area

 

Depending on the state and even the area you're in.
Rest assured that a major metropolitian area in Cali will not be an easy sell for a engine swap / smog certification...They check numbers between body and block etc...
Hell guys in LA are being busted for exhaust cans!

 

[OT] Speaking of emissions...does AZ do emissions testing? I'm thinking of moving there in a year and have a beater that probably won't pass smog. [/OT]

 

The rationale is to retain emmissions functionality that is (presumably) as good or better than the orginal engine.