While they have been out of production for quite a while, the engines produced by AMC are still frequently found in a number of Jeeps, as well as in restored and modified Javelins and AMX's from the muscle car era. The scarce nature of these engines means that the AMC enthusiast will be spending some time searching swap meets and salvage yards for parts. This can be a challenge, but American Motors V8 engines share characteristics with many of the more popular engines produced by GM and Ford, and will respond well to basic modification techniques.

All AMC V8's share a common base design, thus a 304 engine can easily be swapped for a larger 360 or 401. Cubic inches are hard to beat - make the swap if you can, since performance horsepower levels are easier to come by with the larger engines. The "dog leg" heads found on later engines are generally considered superior to earlier rectangular port versions, and should be considered a necessary part of a performance package.

Like the Buick, AMC engines use a timing cover mounted oil pump, which is serviced by replacing the internal gears with a "pump kit". When replacing these parts, particular attention must be paid to the condition of the timing cover casting. Covers with scoring or visible wear will have a detrimental effect on oil pressure, and should be replaced. The timing set is also worthy of careful inspection. Jeep engines produced in 1979 and later use a new timing set that may have been installed as a service part on earlier engines - the newer timing set is NOT a heavy duty replacement, and should not be used in performance engines.

Federal-Mogul offers forged pistons for both the 390 and 401 engines. The L2313F pistons are high compression parts for the 390 which can be modified to work in the 401 if desired.. The L2380F and L2381F are designed for street performance use in the 401 engine. Ductile iron Plasma-Moly Speed-Pro rings are available for these engines, and should be strongly considered wherever severe use or poor fuel quality may be encountered. The O.E. Replacement engine bearings for the AMC are of Tri-metal construction, and should be more than adequate for most applications.

Most of these engines are going into relatively low RPM vehicles for off-road and street performance, thus the selection of camshafts, compression ratios, carburetion, and exhaust components should be on the conservative side. Low end torque throttle response, and fuel tolerance are of major importance in the off road environment.