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It's done all the time for performance applications and can be done for FE, but guessing specs isn't going to be the best way to go about it. You really need a flow bench for the particular head you're working on and some experience on matching the characteristics of the particular engine as well. Since high performance pays, you won't find many FE cam grinds. You could always contract someone to do it, but the cost might not worth it. If you want to do it anyway, you might want to inform the shop of which rpm ranges to concentrate on (the ones you'd use as a cruise speed(s) most often). If you need to send them a head to work from, you might as well have them do some work to it, too. I would imagine some of the HP tricks for lower rpm would also help FE as better breathing reduces pumping losses, but that's a guess.
If you're going that far, you might want to play around with intake runners, also, to maximize the efficiency of the rpm range you're optimizing. The longer the runner, the lower the rpm it helps (when the intake valves close, they send a pulse back through the intake tube. This pulse reflects back whenever it hits a volume of a different size. This pulse can be used to help push more fuel/air into the cylinder the next time the valves open. The longer the intake extends before a change in volume reflects the pulse back, the longer it takes the pulse to travel the distance back and forth. This increases the optimum time between valve openings, which would correlate to a lower rpm. This creates a minor 'supercharging' effect, which may sound bad for FE, but would improve your torque at lower rpm, allowing a smaller load on the engine or taller gearing at a given speed. This should be especially useful on small engines which are generally built for higher rpms as that's the only way the car manufacturers can publish impressive sounding horsepower figures. A notable exception was the EA81 engine in my 1984 Subarus, which made enough torque off the line that I could dust off far more impressive machinery up to about 20 mph, but ran out of breath after 5k rpm. Only had 73 HP as advertised, but if it had been built for higher rpm, it probably would have made over 90, yet been slower in town and probably wouldn't have allowed the gearing where 5th was as tall as that in my Mazda 3). It might not be so easy with modern vehicles using plenums (large volume before the intake runners that lead to the individual cylinders), but spacers between the head and intake could fit, depending on the engine, space available, and about how much additional length you'd need. Why not do this anyway without all the cam work? You could, but it won't have as much of an effect as a tuned system would.
That was probably way more than you wanted to know.
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