EFI computer programing ?

[buknbronco]

This question has probibly been asked, posibly by me, but has anyone gone the route of changing the firing order of a computer versus the cam in an efi conversion. Just wondering what it costs or if it workes.

[Lars]

This question has probibly been asked, posibly by me, but has anyone gone the route of changing the firing order of a computer versus the cam in an efi conversion. Just wondering what it costs or if it workes.

The only way to change the firing order of the computer is to put a chip on it. If you try to do it by rearrange the injector plugs, you'll find that your engine will run like crap. That's because you will have moved injector plugs from one side of the engine to the other. The computer tunes the mixture of each bank of cylinders independently, using the oxygen sensors for feedback. The computer can't know you moved things around. If an injector that used to be on the left now starts making the right side run rich, the computer starts leaning the right side. Except it still thinks the offending injector is on the left side. The ride side stays rich, the computer tries to lean even more, which now makes the left side lean but the right side is still rich, etc. A few people I know have tried it and discovered quickly how it messes things up.

Bottom line. You can do it with a chip, but a new cam is cheaper. Or do nothing and live with the slight roughness at idle.

[welndmn]

Or do nothing and live with the slight roughness at idle.

Mine has been like this for a few years now.
It's aint that bad.

[Broncrick]

Mine to, almost sounds like a nice cam in there at idle

[crawlin68]

I drove my first 5.0 like that for a year or so and didn't notice a rough idle at all.

[Lars]

I drove my first 5.0 like that for a year or so and didn't notice a rough idle at all.

There you have it. Cheap, fast, good.

[crawlin68]

There you have it. Cheap, fast, good.

I don't mean that I changed the injector wires around like you described. All I did was run it without swapping the cam to a HO firing order cam.

[Lars]

I don't mean that I changed the injector wires around like you described. All I did was run it without swapping the cam to a HO firing order cam.

Yep, I realize that. That's the "fast" part

[buknbronco]

Cheap is always good! I guess I will try it with out the cam swap first. See how it runs and weather I like it or not. I may have to swap out the cam anyways, because from what I have read and talking to peeps, since I have a big cam right now it may not have the low end I want for wheeling.

Thanks for the responses. It helps to thing and talk about what I am going to do before I do it. It helps to eliminate mistakes and saves money.