What's the difference between the various "models" of Chrysler 3.3 motors?

, searchable used auto parts nationwide. When youput in the VIN code of your engine, the search results show onlycompatible engines.

OK. Thanks. However I still want to know what the difference is between the differrent 3.3's.

97 is one version of the 3.3. Then changes to the engine for 98 and 99. Most parts interchange between 98 and 99 but not with 97. Mainly due to emissions reg changes. In other words the 97s were one group of engines and the 98-99 were another group of engines. The biggest difference between the G and the R engines is the PCM software. The G engine PCM software is capable of "learning" the use of up to 85% ethanol (E85) in the fuel tank by watching the O2 sensor (called sensorless flex fuel). Alcohol burns leaner. After it learns that there is 20% E in the tank, all OBD2 monitors are turned off. When E content drops below 20%, then the ECM calculates the number of tankfuls of gas that have to go through the engine before OBD2 monitors are re-enabled. The EPA awards emissions credits to mfg's that go beyond certain emissions minimums on a particular engine pkg. They can then use those credits against other engines that don't quite meet a spec somewhere else. It's balanced out by the "total emissions produced" by all engines built. There are people in the auto mfg's that make a living keeping up with this crap. (emissions credits) (not me). Most of the 3.3's between 96 and 2000 were "G" engines, to earn the credits. "R"s would be sold in areas with less stringent emissions regulations.

Bill

98 and newer. I misspoke :) Bill