I have a 1991 f250 with the 460 v8. I was looking into getting a performance chip. All I could find was a chip by Jet Performance. I was wondering if a chip like Bully Dog or Diablo could be used on my truck. Thanks.

 

Chips are a complete waste of time on this vintage truck, you will get the same results buy just advancing the base timing at the distributor. Then the route to more power involves getting more air through the motor, so remove the intake airhorns if you haven't already done so and replace the whole exhaust system and manifolds with headers and whatever you like behind them. After that you got to go inside the motor.

 

So what should I advance the timing to? And would shorty headers add enough horsepower for me to be able to feel it cause long tubes aren't legal in California.

 

Most engines will tolerate 12-14deg initial advance, stock setting is 10 so throw a couple more degrees in and test drive it to see if it pings, if not try some more until you find where it does. Note you must remove the spout plug to disable computer advance before setting the base timing, and the spout plug is located in the TFI harness.
Shorty headers will produce noticable gains if everything behind them is also upgraded, you likely still need a cat but all the aftermarket cats flow more than the stock unit.

 

Doug Thorley makes CARB approved headers, not sure about your application.

Your timing will have to go back to stock for your smog tests.