Those old Fireballs ran pretty good, but if you are groovin for a change, an XE274H from Comp will give you a little more lift and more .050 duration.
Not sure if on the street you'll notice a change but on a dyno it'd make more power with the cam change.
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- 70 Fastback Mustang, 489 cid FE, TKO-600 5 speed, 3.70 9 inch
- 71 F100 shortbed 4x4, 397 cid FE, headers, Street Dominator, 280H, 5 lug Dana 60, 4 speed
