Yup, -187 heads are the TBI "swirl port" heads that don't flow all that great.
Better heads would be any of the 305 H.O. varieties that RB69SS396Conv mentions. (Basically, the heads that were used on the High Output 305's) Stock, they all have the "small-ish" 1.84 intake valves, and ~150-160cc intake runners. -601's have ~55cc chambers, -416 and -081 heads have ~58cc chambers.
I'm running -416's with Z28 springs on my 283 stroker motor and am pretty happy, but they were free and my expectations weren't that high
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I thought the 305 vortec heads weren't that popular due to the lower flow capability. The typical 350 vortecs should work quite well if you can keep the compression up (and you're OK getting a new intake, rocker arms, ...)