I notice that those "speed chips" on ebay are just resistors. Do they work? What kind of resistor is it?

 

they are a joke

if you could get 15~20% more power out of a stock engine safely they would come that way from the assembly line. And if they do actually increase power its at the cost of your engine running in an unsafe state.

 

to answer one of your questions and elaborate on another, No the "speed chips" do not work. The whole idea behind them is that it plugs into your intake air temp. snesor and tells the cars computer that the air is alot colder than it actually is, thus increasing gas to try to make the Air/fuel ratio even. But since there is not enough air to match the gas it really just makes you car run rich.

Now if you are still intrested in trying this out you can do what I did and take out you intake air temp. sensor and plug it into a volt meter and put the tip in some ice water or something that is really cold and read what the volt meter says. Then armed with that info go to a local electronics shop and get the correct resistor for the value of temp. you want. I think on my car (97 civic LX) it was a 100K resistor for what the car would think was 32* air.

hope this helps