Non-recommended Swaps Not all motors work well, or at all, in every chassis. In addition, some DO fit and work, but are still not recommended. Most of this comes down to OBD again. If you haven't read our article on OBD yet, do so before reading the rest of this article. 4th gen * D16Y7/8 * B16A2 (USDM) * B16A3 * 96+ B18C * 96+ B18B * B18C5 * any H-series * any C-series motor We don't recommend these motors for several reasons. The H-series will require much chassis denting, and while that may be cool to do on a race car, it makes your bay look like crap and can lead to a weaker engine bay. In addition, you wont have room for A/C or power steering if those options are required by you.The other motors are OBD-2, requiring a much greater challenge in wiring. The B- and D-series OBD-2 motors can be installed into the chassis fairly easily with a mount kit, but as stated above, the wiring is an absolute nightmare. 5th gen * B16A SiR * B17A * B18A * ZC/D16A6/8/9 * any C-series motor We don't recommend these motors for several reasons as well. These motors are OBD-0, making it a hard swap into a car wired for OBD-1. It is easier to go backwards (as in, taking a 5th gen motor into a 4th gen chassis) than forwards. Remember, its all about backwards compatibility, not forwards. While we haven't listed the H-series motors as a non-recommended swap, we would like to say a few words about it. An H-series motor is generally 60-80 lbs heavier than a B-series motor. This adds to the already poor F/R weight distribution of Civics/Integra's. While it can be solved with a set of stiffer springs and tighter shocks up front, it is still not a good choice for an AutoX or road course car. For drag, it excels. It's heavier, putting more weight on the front wheels to help with traction. In addition to the weight factor, the chassis will need to be modified a little bit to fit it. Some things on the fire wall will need to be moved (such as brake master cylinder) off the wall. The drivers side quarter panel will also need to be dented in a little bit so the crank pulley doesn't rub. 6th gen * B16A SiR * B16A3 * B17A * B18A * 94-95 B18C * 94-95 B18B * ZC/D16A6/8/9 * any C-series motor The reasons for these motors is similar to the 5th gen's, only now we include OBD-1 in the list. When you own an OBD-2 chassis, the easiest swaps are OBD-2 motors. The same general principles apply for the H-series motors as listed in the 5th gen's explanation. 7th gen * any B-series motor * any D-series motor <2001 * any C-series motor * any H-series motor * any F-series motor The new Civic's share the i-VTEC and mounting patterns of the RSX. Neither chassis will accept an older motor. The standard D17 in the Civic or the K20 in the Civic Si/RSX are the new platforms of which Honda hybrid making will be in the future.