Is the '91 318 a Dakota 318 or one from a Ram or Ram Van? The '91 was the last of the LA 318, and the first year for a regular production 318 in a Dakota (1989 Shelby doesn't count). The '91 Dakota 318 accessory drive was unique to it. Uses one year only tensioner, water pump, and I think timing cover but I could be wrong on that. Other than that it was a TBI roller cam 318 with 302 casting heads, similar to all the truck 318s from '88-91.