oh FYI in 85 the 318 got a bump in comp ratio with the closed chamber #302 heads and a taller comp higth on the piston to bump it to 9.0 to 1 comp ratio.

the 360 head will drop that a little but it makes up for it with rpm/flow with the right cam combo. again the 340/360 whiplash in the teen with 360 heads.