Direct quote from
Best Off Road Truck Engine Swaps
What To Shoehorn Into Your Off-Road Rig
From the December, 2009 issue of Off-Road
By Agustin Jimenez
AMC Third Gen V-8
This is one of those oddball engines that are not as mainstream as the other big three's engines but nonetheless it is a great engine that offers monstrous torque. They can be had for practically nothing and if you treat them right, they can live a long life and turn your slow Jeep into a dirt rocket.
Displacement: 304ci, 360ci and 401ci
What they came in: They were produced from '70 to '91 and were available in the Jeep CJ7, Wagoneer, Cherokee, Grand Wagoneer, J-10 and J-20 trucks
Horsepower: 125 to 255 hp
Torque: 220 to 435 lb-ft
Features: Dog leg exhaust ports which build more power than the previous designs, larger piston bores paired with shorter strokes for gobs of torque
Benefits: Inexpensive to purchase at a wrecking yard or online, not a small block Chevy, keeps your Jeep AMC powered, awesome lumpy exhaust note, produces enough power and torque to lift a 39-inch tire off the left front of a CJ-7 under hard launches
Drawbacks: Obsolete parts that can be expensive to repair or replace, stock axles and drivetrain can break under the torque of the AMC V8.
Make It Better: Install a big lumpy cam along with a set of Edelbrock AMC Performer RPM aluminum cylinder heads.
What to use it in: Any Jeep CJ7, Wrangler YJ or TJ that needs to turn massive tires and calls for a V8 that isn't a Chevy or Dodge power plant, would make a great engine choice for a class 3 desert racing Jeep
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