If it is efi it has an ecu, and if it is a CARB(CA smog rig) 22r it will also have an ecu as well, not sure if the non-CA smog 22r's have them or not. However, the pre-OBDII Toyota ecu chips are not reprogramable, they have to be removed from the circuit board and have a new programmed chip soldered in its place. JET electronics is the only company I know of that does this, costs runs about $300, and there is about a 5 day turn around. W/o performing all of the other engine performance upgrades such as intake/exhaust/block/cam/head work/etc, reprogramming the fuel and air delivery wouldn't have much effect, and if you have a carb and not an efi engine it likely wouldn'd have any effect at all.