Need help. 2003 ram 4.7 swap to 2003 5.7 hemi

[Maurice]

I have an 2003 ram 1500 that had an 4.7 motor. I now have the 5.7 hemi i have wiring harness fir the motor and the ecm what else do i need to make this work? I know i need an Electronic gas pedal because the motor has a electronic Throttle body ? Can anyone help me ?

 

[Redtruck-VA]

I don't have personal experience doing this swap but I believe many have used the 4.7 pcm and LSX TB. Custom tuning and its up and running.
I installed a Megasquirt ecm at one point and it required a manual throttle body. I used a LSX 90mm TB. This was when everyone was crying not to use too big of a TB, the hemi didn't like it. BS... it ran great. My current setup is using a BBK 90mm TB with no issues.

 

[HemiLonestar]

My current setup is using a BBK 90mm TB with no issues.

Of course not, blown 392 will eat all the air that 90 can provide lol

 

[Redtruck-VA]

Of course not, blown 392 will eat all the air that 90 can provide lol

Red being a street truck and at wot will boost to 15psi it is driven mostly out of boost pulling a varying degree of vacuum. I also ran this same TB na and have never thought it was too big of a TB. Compared to the LS platform it is small. What I'm advocating is going 90mm or bigger with your TB.