Budget cylinder heads for a 318

jammied said

I agree ... for a 318 use the old 302 castings 1.88 valves or so and some good pocket porting/bowl blending pretty hard to beat. Now when the magnum heads came out they are a out of the box performance head for a 318 and probably the best out of the box 318 head. And without a doubt the best performing factory 318's the factory ever put out. I'm not so sure that the 360 magnum is the best performing factory 360. But that's a different topic

Almost all small block mopar parts available are centered around a 340/360

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Problem with 302 heads not many are into porting so the 302 offers very little in performance gain over stock for most.

Plus 273/318 heads was designed for 273 in mind and not as a performance head. 273 head volume and cfm is in similar ratio with 273 displacement as a X is with a 340, a 318 is 47 cid bigger than a 273 and 22 cid smaller than a 340 less so after an overbore. A 1.88 360 heads would be closer to right if you kept volume and cfm ratio for the 318 the same as 273 and 340.

With and overbore a 318 is 12-17 cid less than a 340 and 0.060”-0.030” smaller than the so called magic 4” bore can see these aftermarket heads being that far off. Not needed for 300-325 hp but for the money can’t see a reason not to. But yes a 1.88 360 or a ported 1.88 302 or magnum heads would right inline with 300-350 hp 318.