I am a bit of a novice to 318s. What are differences between the 1976 318 from a van that I want to rebuild and the 318 in a 1984 Ram150 that I want to put the rebuilt into? Will the 1976 rebuilt fit the tranny in my 1984 automatic? Engine mounts the same? Emissions the same? What should I pay attention to or watch out for? I assume both are LA 318s; neither has fuel injection. I want this to be an easy swap, so if it is not, please give me some advice. Thanks for helping!

 

If I am understanding you correctly, you want to take a 76 318 and rebuild it to replace an 84 318. Why don't you just rebuild the 84 318 and retain the emissions and any new technology and "improvements" that came up since 76. In 84 I believe you may have the computer. I'm not sure when computers were first put in but if so the wiring harness from the 84 will need to be used. Just re-use the motor mounts from your 84 since the block attachment should be the same. One thing that may be worth considering, is if one or the other is a 4 barrel carb. I would go with that one's intake and I believe the heads on a 4 barrel motor may flow better too but I could be mistaken. I don't believe that horsepower from 76 to 84 is even worth considering since both are probably pretty close. If you do decide to go with the 76, the bottom end should all be the same. Mounting to the tranny should be the same as well.

I just think that you are switching from an apple to an apple. If you need to rebuild it anyway why switch at all, just rebuild the original motor.

 

The reason for considering the swap is so that I could give the rebuilt, as a gift, to my son who lives 2000 miles away. The engine in his 1984 is getting tired, but it is not quite ready to go, and the rest of the truck is in great shape. I thought I could rebuild one over the period of a few months, spruce it up really nice, add some upgrades, and present it to him when he drives home in a few months. Thanks for the suggestions about the computer and wiring harness. Since I have time, I can look into that issue; maybe I need to try to find an '84 to make sure that it is a straight forward swap. I am 100% sure the engine in it now is original as the truck has always been in our family.

 

You may want to consider purchasing a long block for that year and then transferring your needed parts from the original motor. This would save time and then turn in the old motor for the core charge after the swap.

 

I don't really think you have anything to worry about. I think the only mechanical difference is that if the 84 is late production, and has an 85 motor, it could have a roller cam and 302 heads. But if you are spicing it up, that probably won't make a difference anyway. But i could be totally wrong here.