340 camshaft

has anyone ever used an isky mega cam before ? my 69 dart has a rebuilt 340 9.75 compression, rpm intake 650 double pump carb, lightly ported big valve j-heads, headers with dual exhaust, 727 with 2400 converter,and 3.55 gears, I was looking at an isky 270 mega cam, I am new to mopars and would like to know what would work best, looking for something fun on the street and would pull hard to 6000 rpm and run low 13s to high 12s, any help would be great.