I was wondering about adding fuel injection to my 78 el camino but i had a few questions to ask. Right now i have a pretty pimped out 400ci small blocked that has been upped to 406ci. How much of a horsepower increase would i get and what would be the effect in my fuel consumption? How much will everything i need run me? What are all the things i need? What is the difficulty of the install?

I too am planning on installing fuel injection on the motor I'm building. There are a few manufacturers that make what appears to be a nice setup, I have chosen to go with the Edelbrock Performer Plus setup. I chose it for the fact that you do not need a lap top PC in your car to fine tune it. It is expensive. Accel also makes one, also expensive. You can also install a factory setup that came on newer GM vehicles such as Vettes Trans Ams or Camaros and a few others. Aftermarket setups are available in different CFM's, this will effect fuel economy depending on which you choose. I think that if you stay with a more streeable setup, you will see an increase in miles per gallon over a large CFM carburator, better performance, and a smoother running engine. If you have the cash to do the conversion, I think it is money well spent. It could cost anywhere from $1000-$2500 approx. to do the conversion. A fuel injection system out of a donor car would be cheaper then a new complete system from Edelbrock, however ease of installation also comes into play here. I think that the Edelbrock system would be an easier installation. If I am not mistaken, your year Elky would be the easiest of the 5th gen Elkys to convert to fuel injection being that the 78 Elky has no ECM installed.