huh...and here I figured the best bet to run EFI on a 460, would be to leave the stock EFI parts on the stock 460 that came in the truck from Ford...didnt know I had to spend a bunch of money to make a stock system work
just poking a little fun, so dont get bent out of shape over it
I know I would need to swap to a MAF system, and have a PCM programmed to really do anything with the engine, and that the stock speed density sytem wont be able to make the necassary changes to the fuel maps.
from what I have found, the heads are interchangeable on the blocks, but the intakes are not backwards compatible, meaning the carb heads can be made to work with EFI intakes, but the EFI intakes will not work with the carbed heads because the port height is different enough to open the ports into the lifter valley
I have not removed the D3 heads from the other 460 that I have sitting on a stand to verify this for myself, just the info I have been able to find on the net, from several different sources
what I have decided on is this: I will do a basic rebuild on the stock 460 that originally came in the truck, and reinstall it in the truck. Later, I will build up the other 460 I have on a stand, with the D3 heads, and build my own intake to run EFI on that engine ( I have a plan for that, so just drilling holes and welding bungs into a stock intake wont work with my plans), and get all of my pieces togethor, computer, wiring, etc. When I have that engine ready to go in, I will pull everything out of this truck, including the speed density system, and install all the new hi-po stuff, and then the existing 460 with the speed density system can go into my '78 F250, which will just be my tow rig when I get it done anyway, so that system will work fine for that.