I'd like to add a supercharger to my R/T Plus with Shaker. Besides the supercharger unit, will I have to buy larger fuel injectors? Need a new rear end? What else would I need to change to make it work with the 5.7L. Thanks,
https://magnusonsuperchargers.com/collections/dodge The Magnuson kit doesn't require larger injectors. Mine benefitted from a larger intake capacity and full exhaust. I also went to a 3.91 diff ratio in an automatic which wouldn't be practical for those spending much time hiway driving. You can view the complete installation instructions on their site. They've provided me with excellent support despite not being the car owner at time of install.
Welcome to the forum first of all. here is another good super charger that my shop has installed, here is the link. https://www.procharger.com/superchargers-for-challengers/
There is nothing wrong with the 3:91 gear ratio on the highway. I have ran this ratio and higher in my cars and trucks for over 50 years. Plus with the new 5 and 8 speed transmissions they have great overdrive gears in them.
And I would invest in a good one-piece drive shaft. i you want to replace the complete rear end assembly it is not that hard to do. After you put the car on a lift or rear tires on ramps remove the driveshaft, brake lines and mounting hardware, lower the unit and the axles will slip out of the differential as they are not fastened inside it.
The 3.91 diff ratio in my 2010 5 spd auto is not practical (particularly on hiway) only from the aspect of noticeably increased fuel consumption due to motor revving higher. My 3.91 LSD diff came from a manual trans car of a compatible year and required dual axle replacement.
I guess it is what a person is used to. I ran 3.91 and 4.56 in my 440 cars back in the 70's with the 3 speed torqueflight trans, and thought nothing about it. I have 3.92 in my 17 truck and the rpms are low even at highway speed. I am not sure about your rear end because I can see the difference between the ones in my 13 RT and 23 RT.
Steve White performs this mod using Magnuson and Petty Garage have performed same mod with Procharger, both with functional shaker, but I haven't read a description on how specifically.
