You don't want 360 heads on a 318 unless you can do something with the compression. They will drop already low compression to the basement, unless you use something like the 302 heads
Why i said mill, you need to take something like .030-.040" off to have same chamber size as 318 heads, 302 heads are just like any other 318 don't flow enough and the CR advantage get ya like 2% power increase that's like 5hp, 10hp at best, if you want closed chamber magnum would be a better choice and can handle 400hp without porting. LA 360 can handle around 375 hp without porting.
318 heads 300 maybe 325 hp without porting. were talking low cr and reasonable cam sizes here for power output.
