The following equipment was added when you ordered the Hemi engine. 

The Hemi was only available with a Charger R/T or a Charger Super Bee.

 

  Standard Equipment
D34 TorqueFlite Automatic Transmission (std. on R/T); with a Hemi, the transmission had a 5 clutch pack instead of the regular 4; it had a special yellow transmission mount that used 5/8" bolts and it had a special 2650-2800 stall torque converter that used 5/8" nuts
E74 426 Hemi Engine; consists of:
  425 HP @ 5000 RPM; 490 LBS/FT @ 4000 RPM
  4.25" X 3.75" Bore and Stroke
  90 degree OHV Cast Iron Block; Cast Iron Heads
  Aluminum Dual Plane Intake Manifold
  2 X Carter AFB 600 cfm Carburetors
  2.25" Intake Valves; 1.94" Exhaust Valves
  Hydraulic Camshaft; .484" Intake Lift and .475" Exhaust Lift
  Dual Point Ignition Distributor (IBS p/n 4017 for Auto Hemi's)
  Forged Aluminum Pistons; Forged Steel Crankshaft
  Forged Steel Connecting Rods
  5 Main Bearings
  2 1/2" Cast Iron Exhaust Manifolds
  Red Line @ 5000
  Manual Choke - cable attached to a handle under the dash
F25 70 Amp Battery (std. on 440's and Hemi's)
N42 Chrome Exhaust Tips
N51 Maximum Engine Cooling (26" Radiator)
N75
Auxiliary Transmission Cooler was added with Auomatic Hemi's; it came with a clip attached to the starter to hold the transmission lines
N96 Air Grabber Ram Charger Hood Scoop
 
Body Plates: the following 4 areas under the car were reinforced with extra steel plating: 1) the pinion snubber area (Hemi only); 2) a torque box was added where the front of the rear leaf spring is attached to the body (440's had this too); 3) the front of the torque box had an extra steel plate (Hemi only); 4) a plate on the body where the rear of the leaf spring attached to the body (440 Chargers in 1971 had this too).
  Exhaust System: resonators were added to the exhaust system; these are located at the rear of the tailpipe assembly just before the exhaust tips; two exhaust heat tubes were added on the exhaust manifold to the back of the intake manifold. This allowed hot exhaust gases to heat up the intake manifold quickly.
  Fuel Line: were increased to 3/8" from the regular 5/16" (on 440-6V too).
  K-Frame: unique to Hemi cars as it had an extra skid plate on the bottom and Hemi engine mounting brackets; the K-frame part number is 3583076 and "76" is stamped onto a welded coin plate at the front of the K-frame. 
 
Master Cylinder: a unique master cylinder was used for Hemi engine cars: one for power brake cars and one for manual brake cars.
 
37 Amp Alternator was installed on Hemi cars; this alternator had 2 pulleys even though only one was used
   
  Optional Equipment
B11 Power Brakes: when ordered with a Hemi, an offset bracket was attached to the brake booster so that the driver's side Hemi valve cover could lift off easily.
D21 4 Speed Transmission (n/c option on an R/T): when ordered with a Hemi (and 440's), an 18-spline input shaft was used instead of the regular 23-spline shaft.
   
  Mandatory Options
S15 HD Suspension (std. on R/T but optional on the Super Bee)
   
  Options N/A with the Hemi
A35 Trailer Towing Package
H51 Air Conditioning
J24 Washer System for Concealed Headlights
N88 Speed Control
W34 Space Saver Spare Tire