Rules regulating engine swapping are not make/model specific. The simple rule is that a vehicle must have all emissions components that were present when it was manufactured, which may include:
Read more information about emissions tampering regulations.
All vehicles used on the public highways are required to meet all of the state equipment laws and requirements; therefore, reconstructed or rebuilt vehicles which are using the public highways are also expected to meet all of the state equipment laws and regulations. Reconstructed or rebuilt vehicles in many instances fail to meet state requirements and, therefore, are not legal for use on the public highways.
All reconstructed or rebuilt vehicles (sand or dune buggies or hot rods) must comply with inspection requirements for the class of motor vehicle it is being inspected as, such as car, truck, motorcycle, or motor-driven cycle.
Be sure to check reconstructed or rebuilt vehicles for all required items of inspection with particular attention to the lighting devices. Head lamps shall be of a type acceptable by the Department. No modifications are allowed that will change the original design or performance of any lamp. Only acceptable automobile head lamps may be used on cars and trucks. Either the 7-inch head lamps or both dual head lamps (type 1 and type 2) may be used. Only acceptable motorcycle head lamps may be used on motorcycles, motor-driven cycles, and mopeds.
All lighting devices must be of an acceptable type that meet Department standards and must comply with the mounting heights as specified in the inspection requirements.
The year model of a reconstructed vehicle will be the same year in which it was reconstructed and not the year of original manufacture. Therefore, the inspection requirements would be for the model year of the vehicle (same as the year of reconstruction) or the year model of the engine itself, whichever is the later model.
Motor vehicles used for competitive racing, such as modified stock cars, dragsters, and hot rods may be inspected. When such a vehicle is presented for inspection, all rules and regulations regarding the inspection of the vehicle will apply. This applies to brake requirements, exhaust systems, as well as any other item required in these provisions.
Vehicles have to meet the emissions standards for the year the vehicle is assembled. Vehicle manufacturers have to certify that their vehicles meet EPA emissions standards. A lot of kit car manufacturers also comply with this requirement. If you purchase one of these kit cars, follow the instructions on assembly, including the emissions components. You should be able to pass an emissions test just like any other new car.
Just as the EPA does not allow an individual to reverse engineer a vehicle to defeat emission standards, they do not allow an individual to build a brand new "old" vehicle to bypass emissions standards. It is possible if you actually use old parts (like a 1965 engine, or complete 60s frame and powertrain) that the vehicle will be registered as that model year (replica), but this is a TxDOT issue. However it is registered, is how DPS inspection stations will test it.