Unfortunately it will hurt something. The 318 is internally balanced, while the 360 is externally balanced. So the 360 plate is heavier in certain areas to balance the rotating assembly. While these balancing weights correct for a 360, they will cause your 318 to be unbalanced, which isn't good.

 

Looking at the pics of the 2 the only difference is some small holes drilled into the 360 plate. Gotta be less than than 4 gram difference.

 

Your motor

 

Next question. Did you use the torque converter from the 1994 truck? If so, and if it was a 360, it has balancing weights on it as well. With a 318 you don't want NONE of that.

 

Not for long. Im gonna finish it up and sell it immediately. But i would like it to be right. I suppose the easiest way to fix it is to pull the tranny but i do not have any help. It was hard enough getting the motor and tranny in as one by myself. If there was a weight on it shouldnt i just be able to remove the weight? Anyone have a pic of a 360 flexplate with a weight?

 

YES. *** me. Gotta pull tranny out and change both the TC and flexplate i guess. And i dont have either of them.

 

Ok next question if i pullthe tranny can i still run the engine so i can continue to work on it?

 

Will it damage running it with in in park?

 

I was able to start mine with no trans. As long as the safety switch thinks it's safe (the one that won't let you start in anything but neutral or park) you should be able to.

Do you not have the flexplate that came with the 318 from the yard?

 

Yes i do and it looks identical to the 360 plate. The motor came out a 2001 supposedly. I dont know if that makes a difference. I bought the motor from an indiviual at 10 pm after having worked a 14 hr day and i guess i just failed to check the stamping on the block.