Found this on e-bay, is it real or a joke??

[84LX89GT]

You can get that resistor at a radio shack for like a $1. The idea is to have a higher resistance, lower voltage value back to the pcm at operating temperature for the IAT sensor (air coming into the intake tract) and since colder air is denser, the PCM will richen the mixture and advance the timing slightly so the engine will pick up a little bit of power. The resistor is a fixed value so the Powertrain control module will not vary it's operating parameters as much to the conditions for a short time. Not only that, but at part throttle is where fuel trim is determined from the oxygen sensors and the processor will eventually learn the car is running rich anyway and cut back on fuel trim, which negates the whole point of installing a resistor. If you install it right before you race then it will run richer for a short time, or if you disconnect the battery and reset the fuel strategies. If you want to go drag racing it may be worthwhile to possibly pick up a tenth or maybe a mph.