I scrapped an October-December 1984 318 with 302s and the drilled holes for the spiders- but being a truck motor it had a flat tappet in it. '85 is when that all started, and the late '84 builds could have it if they didn't all. Truck and cop car 318s had flat tappet cams in roller blocks until the trucks got TBI- weird since they quit making 4bbl truck motors when the roller motors came out.
The big place you'll want to gain is in the mid-range. Worth keeping in mind that "upper-end" in these motors starts in the low 4000s- if it's all stock that's where it's laying over.
If you're rebuilding the 318 upgrading from the 302s to something better would be a sound idea. The valve springs stock are basically all tailor fit to the what the OE engine was built for- few times will you change cams and not need to change the springs in any of the motors. A pretty much E48 style build with roller cam and some additional improvements would make a very good DD motor.
