5.7 swap

The factory ECM is an option. This is basically what Hot Wire Automotive uses, they use a factory service tool to access a series of menus to turn on and off certain features. For example, if you plan on using a 904/727 or a manual transmission, Hot Wire simply selects the manual transmission option in the service menu of the factory ECM. Think you'll simply buy your own service tool? They run about 4K on ebay. OUCH.

Certain years have advantages over other years.

The 2003 Hemi ECM is the most primitive and a little unfriendly, it had a separate controller for the transmission. Most people transplanting late model Hemis into classic muscle cars avoid them.

The 2004-2006 are arguably the easiest to make work in classic muscle cars for the following reasons:

1. Only '04-06 California (and states that have CA emission standards) computers utilized O2 sensors before AND AFTER the catalytic converters. So you only need 02 sensors in the left and right bank.

2. Not all 04-06 computers utilized a SKIM key. The Skim key is an anti theft device that is basically an RFID (Radio Frequency Identification Device) that creates a handshake between the key and the cars computer. No Handshake=No Start

3. The 2004-2006 Truck 545RFE is the easiest transmssion to put in a muscle car (obviously excluding the major surgery to your floor pan and cross member) because the speed sensors for the factory computer are located in the transmission itself. The car transmission utilizes the same wheel sensors for the ABS.

The following has been done successfully, it takes planning and diligence, but it is the cheapest way to get the hemi running in your car.

1. Find a suitable Hemi that is running, in a truck or car.
2. Remove the engine and transmission.
3. Remove the engine wiring harness.
4. Remove the engine power distribution center, complete with relays for the fuel injection pump, and relays for the ECM.
5. Remove the under the dash wiring harness, including ignition key, and OBD port.
6. Buy a copy of the factory service manual, the factory service manual will provide a complete wiring diagram and explanation of the various circuits and their function.
7. Using the factory servie manual begin tracing each circuit and remove the circuits you don't need, and keeping the ones you do need.
8. If you are using a factory transmission, and all the factory sensors you probably won't even need the factory service tool.

Regards,

Joe Dokes