I currently have a 91 F250 with a EFI 460.
Currently it has:
Gibson headers
3" Exhaust
K&N Intake
180 Thermostat
In the middle of putting in a FF X4 256H-11 Cam, along with a 68 timing set.
I know with this addition it's going to make my truck run like crap without tuning. I've heard a lot of people say that you can still run a decent cam with out worrying about the Speed Density system so I decided to. As for tuning, I still have plans for the future, maybe light porting, larger TB. Should I go ahead and get the chip made for what I currently have, or should I have it made for what I want in the future, or what?

 

You're going to have to get the chip reprogrammed if you plan to make future changes and only you can determine if its worth the extra c-bill to custom program the chip again.