Frankenstein318

Ok So I am in need of some help again. I have been working on this car what seems like forever and I have not gotten very far. A little background on the car, 1974 Plymouth duster originally a slant 6 car, still has the 904 transmission and 7 ¼ rear… that is what I know. The engine is where things get exciting. When I bought the car in 2004 it had a 318 two barrel on it. And it ran great. Just got tired quick and was in need of a rebuild. I went out and bought a refurbished 318 from a friend of the family. I did not think to get the build specifics from the guy. I figured it would be a plug and play…lessons learned I guess. So here is what I KNOW (this list will be short) I know the engine is stamped 4006730-318-11as far as I can tell this is a 318 block used from 1976-1984. The heads are stamped 3769973 1975and as far as I can tell that means they are 318 heads that were used from 1975-1983 but with the date stamp of 1975, I am going to go with 1975. The intake is stamped 4173915 2 and this is a little harder to narrow down I get conflicting information on it being for a either a 318 or a 360….date stamped 2-13-81? The distributor is stamped 411150 and I can find 0 information on it. I am running an Edelbrock 1406 650 CFM carb (brand new outta the box).

Ok so now that I have told you what I am working with, can anyone tell me if this combo is compatible with my car? Or even if this engine combo will ever come together and work? I have been fighting the timing on this car like no other. Right now I have set the base timing at 12 BTDS and it runs good, no ping, no back fire, (BTW the engine has less than 300 miles on it)..but the car acts differently every day. I have gone through the carb 4-5 times thinking that was an issue, but I think I have it narrowed down pretty sweet. The car pulls great vacuum (right now at idle it pulls 23 HG of vacuum from the manifold side not the ported side because that is where the vacuum advance gets connected…learned that on this website). I guess the question I am asking is this… am I chasing my tail on this car or will this set up work. I have heard all sorts of “if it where mine….” Most involve me tearing the motor back out of the car or spending a bunch more money to replace heads or intake or take the cam out…… hopefully my mad typing makes sense to someone out there. Maybe this is more or a rant than anything else. Oh and I can and will supply pictures of anything if it will help clear the mud.. thanks