I've just got my act sensor sitting on top of the lower intake. Is that ok(will it hurt performance?) or do i need to tap it into the maf to tb hose somewhere. I'm not going to tap the intake.
The ACT (Air Charge Temp) sensor will probably need to be moved. The GT 40 lower manifold isn't drilled & tapped for it to go into the intake like the stock manifold was. There is a boss cast into the GT 40, but a machine shop will have to drill & tap the new manifold. The best spot for the ACT is the air box if you don't do the drill and tap thing. You get to cut and splice the 2 ACT wires in order to make them long enough to reach the air box. Solder the wire extensions on the existing wires & use heat shrink tubing to cover the splices. Offset the place where you cut the wires so that you don't have a big bulge when you put heat shrink over the 2 wires to cover & protect them. The air box gets a hole (5/8" or so) for the ACT drilled about 1 1/4" down & 1/1/4" in on the front top side near the upper radiator hose. A brass fitting nut from Home Depot or Ace Hardware secures the ACT into the air box.
If you are very clever, you will find that the ACT connector comes apart so that you can remove the pins. A very small screwdriver releases the lock in the front of the center insert, while another small screwdriver inserted in the back pushes it out. Once the center insert is out of the connector shell, the pins come out easily. New pins are available from AutoZone in a $5 electrical pin kit for Fords. Crimping the pins on the extender wires saves you from having to splice them twice: once to put the connector on and once to extend the wires.
6 ft black 18 gauge wire
6 ft green 18 gauge wire
6 ft 1/4" heat shrink tubing
1 ft 3/16" heat shrink tubing
It's there to measure the temperature of the air entering the engine. You're measuring the air temp. right above the intake manifold. As long as one is close to the other - it probably won't make much difference. When they're far apart - it will make more difference. The fox body computers seem to be pretty unaffected by ACT sensor location. If it were mine, I'd lengthen the wiring harness and install the sensor in the piping before the throttle body.