[Mr427]

Mr. Bassn:

What you are looking for is extreme low end torque. The truck engines in the FE line were superb heavy haulers in all forms. the biggest of them, the 391 has to be among the strongest engines evr put in a truck.

Torque in your engine is only usable at low rpms, say, from 1500 to 4000. The parts you put in that engine should be singularly chosen with the highest possible air velocity in the rpm range that you will use it. So, do not install drag racing parts in this engine, whatever anybody says. Stay with small valves and ports. The truck engines camw with valves in the small range: 1.95 intake and 1.55 exhaust. They guarantee that you can pull away with a heavy load in high gear from 20mph and 1500rpms without backfiring or hickups.

Use a long runner dual plane intake, such as the Edelbrock RPM, Weiand or Offy. The old GT-390 intake can be found at reasonable prices on E-bay as well as the 428CJ iron intake. Use a brand new small CFM Holley or Edelbrock. The Carter 625 is an outstanding carb as well. Stay away from double pumpers or carbs with a progressive secondary function.

Use a very conservative cam, no more than 210 to 218 at ,050 lift and with a lift no more than ,500" Stay with the stock valves and heads, they are a perfect match for your trucks´weight. If you can and want to go to the longer stroke of the 391 that is good too, but make sure you have the correct rods and pistons with it.

Install a set of RV headers with primary tube diameter of no more than 1 7/8 and a matching tube length for the weight.

If you are going to install new pistons, stay on the conservative side with compression, no more than 9 to 1 with a max of under 10.

Buy roller tip rockers if you can afford them. Use the best ignition that your money will buy.

You will be happy with that formula.