Injector upgrade
 

If i upgrade to bigger injectors, how bad will it kill fuel millage?

As long as you keep your foot out of it, :w2: little to none! :tu:

Depending on how wild you go most of the time after the excitment wears off you will actually see better mileage.

yeah new injectors should help your milage if yours are 20 years old. just keep your foot out of it.

As long as you have adequate air it will not hurt economy. If you're making tons of smoke that will hurt mpg's.